<1000 ELO, Victory but want to know if my line of thinking was correct...

Ok, so I have a hard time understanding certain lines, so I'll go through this the best I can.  The reason why I posted a victory is because typically I can look at a game and see where and why I lost (greedy, falling for traps/gambits, etc.), but I very rarely understand why I win.  In this game in particular, I can see where I properly applied pressure to my opponents pieces without risking my own, but I don't think this is a game I should have won.  My opponent made a million blunders, and I shouldn't have been in the positions I was in... I've posted my line of thinking, and I'd like feed back as to whether or not my thinking is even in the correct place.  I'll be posting a loss here shortly so I can get feedback on that as well.  

Honestly, I want to improve at Chess.  I've never played a game that uses ELO where I haven't been 1600+, and I've even played games where I was close to 2100 (in Magic: the Gathering) at points in time, so the fact that I can't even get to 1000 bothers me greatly.  I feel as though a LOT of games will help me, but at the same time, the transition from the Opening to the Mid-Game and seeing the tactics (and not falling for them!) is my biggest weakness, and I think this game shows an improvement for me.  The computer said the following moves were errors, and I'd like to know why:

5d3 should have been Nxd4, but I feel as though making him decide to trade keeps my second Knight safer, and moving the pawn allows me to maintain some semblance of mid control.  

11Qh3 should have been Nd5.  I get that I can check the next turn, and it forces him to take my Bishop with his Queen to avoid losing it, but I don't lose a piece here, and while I can take his Rook in two moves, I don't see that being more beneficial than a slower, safer game.  At all.  I can't even begin to understand this.  

Bd7+ BLUNDER - You had a slight edge but threw it away with that last move. The best move was 12. Nd5

How is this a blunder?

(0.91) INACCURACY - Perhaps better was 16. Bxh6

I'm not sure why this is an inaccuracy.  

17axb3 vs 17 cxb3 - What is the tactical difference here?  I know there is one, I just don't know what it is.

22 Bg5+ is better than Qh4+ but I don't know why...

So, a lot of questions, and I don't know if I'll even get any answers.  If anyone wants a "blank slate" to work with, I'm your guy.  I will listen, no matter how uncomfortable, I'm a student of any game I play, and love to read, etc., so I would be an excellent pupil for anyone willing to teach.  Otherwise, please let me know how absolutely awful I was in this game.

Bd7+ is already losing. If the black queen takes it, you lose a piece.

I didn't analyze it with an engine (no time), so people feel free to correct me.

5. d3 Bg4. Pinning the knight, and excluding exotic lines with sacrifices, black can force you to play gxf3 after he takes your knight with either ...Bxf3 or ...Nxf3 leaving u with double pawns on the f-file and O-O is more dangerous now.

11. Nd5, forcing the queen back to her starting square, which is something you rarely want to do.

12.Bd7+?? Qxd7 and you are a piece behind for no reason.

16. Bxh6 gxh6. No one likes to have double pawns on the h-file and thus no pawns on the g-file.

17. axb3 puts your rook on the semi open file, and rule of thumb says always capture towards the center.

22. Bg5+. Possible options for black:

22. ...Be7 23. Bxe7+, and you are a piece ahead.

22. ...Ke8 23. Nxc7+, forking king, queen and rook.

22. ...Kc8 or Kd7 23. Bf6 Rg8 24. Qxh7 which gives black a very uncomfortable position.

I stopped looking at the game when you dropped a piece with 12. bd7 and couldnt figure out why the computer thought it was a blunder.

At your level, the best thing you can do to improve is practice tactics.  Suggest a free account at chesstempo.com.  Talking about the game with you is just not a substitute for practicing tactics, and you arent going to improve much until you can spot basic blunders like bd7.  

Did the computer say 5.d3 was an innaccuracy, mistake or blunder? There are big differences! To me it looks good, but a slightly less optimal response than NxN. NxN swops his well developed, dangerous N for your less well developed, passive N. He's also left wuth doubled pawns one of which is quickly attacked by your N necessitating another pawn move in defence - and then you can develop another piece and you're well ahead in development! 

You may prefer a "slower, safer" game that might beat a 1000 player, the computer likes *the best* game, i.e. one that can thrash Magnus Carlsen. This means you are bound to encounter *better* tactics like 11.Nd5, that you will always miss, but the computer never does.

Note these aren't "fast, unsafe" tactics, they are just *better*. Rather than dismissing the computer as "fast and unsafe" you'd be better showing some humility and recognising *better* tactics that you can (perhaps) use in the next game. Then again, siome computer tactics are so complex that you will never master them. Then you should just shake your head and smile.

The best computers can see tactics that Grandmasters would never see, so don't expect to ever become as good as the computer. This is a kind of ultimate humility! No one will ever be as good as the best computer, just as the best sprinter will never run faster than a greyhound.

12.Bd7+ loses the bishop as your opponent should have played QxB. Before moving to d7 you should have counted how many pieces were defending that square (answer: 2, K & Q) and how many attacking (answer:1 only your Q, AFTER B had moved there). This is the simplest of tactics, that even I usually manage to see. Maybe you should be playing longer games (45 | 45) if you are missing things like this - then you have time to check everything carefully. 12.Nd5 look slike a wonderful move. I'd listen to Mr Computer. He's always right :)

17 axb3 opens up the file for your rook to attack your opponent's pawn. Imagine the damage that b4 or Bd2 could then cause... Try reading "My System" by Nimzowitsch - he's very good on exploiting open files and such tactics/strategies.

Hope these answers help, if not, remain optimistic about getting answers. Many people here are very helpful , and I hope they'll chip and tell me bluntly if I'm talking rubbish .

I don't think you were at all awful in this game, it's just the computer pointed out some slightly better tactics and positions - the only massive blunder was losing your bishop (although your opponent didn't captalise 'cause its was the type of blunder we all make/miss at at the 900-1400 level!)

Finally, I don't think there are simple rules for not missing checkmate. The general advice is to do tactics problems repeatedly half an hour a day for a decade then you might be a bit more likely not to miss checkmates.

Bd7+ was a terrible blunder. You're losing a piece and a pawn for no compensation. Especially given the fact that black was having difficulty getting his king out of the middle of the board, Bd7+ drops the bishop for nothing and eliminates his castling problem all at once and you can't save the pawn on c2 either.

I hope this helps. I'm not that great myself but I have a lot of experience with beginners. Let me know if you don't understand something.

Hello everyone!  I haven't read through all of the comments, but I wanted to address a few things really quick that I've noticed in the few I've read so far.

By no means am I questioning the computer, though I think internet speech etiquette makes it seem as though that is what I am doing... I'm just looking for explanations as to "how" it's a blunder.  Now that I see that the "blunder" wasn't capitalized on by my opponent, it makes much more sense why it was a blunder.  If he takes my Bishop with his Queen, my only "recourse" for taking a piece back is by using *MY* Queen, which will make me lose my Q+B for his Q.  That makes a lot more sense (Someone specifically mentioned that it's the type of blunder all beginners miss, so that explains why based on my opponents moves, it is most certainly a blunder, but not one that was easily noticed by me).  More importantly, my "tone" I guess regarding the "slower, safer" game probably seemed questioning the computer as well, and I definitely didn't mean it that way... more I was looking for affirmation as to whether my move was adequete when playing towards a safer game, or if there is 100% always a clear cut correct/most correct move in situations like that... if that's the case, then why is making the more aggressive move "better"?  Is it due to positional advantages gained?  

I'll read through the rest of the comments, I did want to clarify that I'm not questioning or anything, I really am a blank slate, however sometimes when typing on the internet inquisical "tone" is dropped, as all you guys get to read is context and typing, and in this case, context can be related to the "majority" of beginners like me who post... and then try to ignore/question advice given.  I assure everyone, I am not that person :)

Thanks again for all the replies, I will read through them and see if I can learn a lot of stuff that I can apply.  I do practice tactics quite often, and I've been watching high level chess and trying to understand their reasoning, and then I've been replaying myself through my games to see what I would have changed in hindsight... 

Sure Sarkhon, as everyone else said, nothing unusual, all beginners go through the same things.  All I'm saying is that if you are told bd7 is a blunder, look at it again, and it doesnt jump out, that shows where you are at tactically.  No shame there.  But given where you are at, training tactics will help a lot.  Chesstempo.com is like the tactics trainer here, except unlimited problems for free, and a lot more flexibility.  Its actually a lot of fun.  You get a tactics rating (just like here) and can watch it improve as you improve (although it will probably fall at first, since the starting rate is likely too high for you.)  

Awesome! I just didn't want to get the stigma that I'm unwilling to listen or learn is all :)  I know on some other sites when I give advice to new players who seem to, or don't take the advice, it almost black balls them forever from getting advice!  I'll definitely check out chesstempo though!