Italian opening + evans gambit.

I'm new to chess. Been playing for about a week now, and i'm trying to learn my first opening. I found a forum thread where few players suggested, that the italian opening is a good one to learn for a beginner. I also found this evans gambit move on youtube which i really like, so i decided to start with this one. But i have couple of questions in case something goes different than usually in this opening. I'll write down the moves and put my questions in brackets.

So the moves goes like:

1.e4 e5(if black doesn't play e5, should i still follow with the italian opening, or answer with something else. I played a game with my grandpa, and he did a c5 move. What would be a good response in this situation?)

2.Nf3 Nc6(if black plays d6 to protect  it's e pawn, should i still follow up with the italian opening?)

3.Bc4 Bc5(now, if black doesn't play Bc5, what should i do? Yesterday i had a game, where blak played Bb4. I still followed with attacking the weak f pawn on black side by c3, then black did Ba5 and i did Qb3. Basically i achieved the same position i was aiming to achieve by using the evans gambit, but without sacrificing two pawns. But if black doesn't play the bishop to c5 at all, should i still follow with the attack to the weak f pawn, which is the whole point of the evans gambit move?)

And this is the point, which interests me the most:

4. b4 Bxb4(if this happens, i basically achieved what i wanted to, but if black decided to retreat the bishop to let's say Bb6. What should be the proper response?)

Openings are currently my weak spot, cause i calculate pretty well to figure out possible outcomes of different moves, but i really don't know what way to develop my pieces if something happens the way i didn't expect it to. Thank you for your help, guys! :)

The Italian is e4 e5   Nf3 Nc6    Bc4

Use the game explorer and see what masters play.

In most cases you mentioned it is possible to follow with 3.Bc4, however, not blindly. You must adapt to your opponents moves.

For example 1.e4 e5 2.nf3 nc6 3.bc4, the italian is quite good, the bishop on c4 tragets blacks weak f pawn.

Now if we were to change the moves

1.e4 e6 2.nf3 c6 (not a very good move, but it illustrates the point) 3.bc4, now 3.Bc4 is not so good. For starters the f7 pawn is no longer weak because the e6 pawn is blunting the scope of the bishop (this pawn was on e5 in the italian, weakening the a2-g8 diagonal toward the f7 pawn).

In addition to this black will likely follow with 3..d5 when the bishop will be attacked and have to move again in a couple of moves 4.exd5 exd5.

Even Grandma Roman got it systematically wrong:

The Italian game is not

                         e4 e5   Nf3 Nc6    Bc4

but                    e4 e5   Nf3 Nc6    Bc4 Bc5

http://www.expert-chess-strategies.com/italian-game.html

http://www.youtube.com/watch?v=GI-R816VxQ8

http://en.wikibooks.org/wiki/Chess_Opening_Theory/1._e4/1...e5/2._Nf3/2...Nc6/3._Bc4

http://exeterchessclub.org.uk/content/italian-game-beginners

Just in case somebody is looking for good book -Yakov Estrin Italian game-

No, 1.e4 e5 2.nf3 nc6 3.Bc4 is the italian game.

3..Bc5 is the Giuoco Piano ('quiet game').

If you are too lazy to look....

The  denominator is the 4th Black move, for example -4.  Nf6 is characterizing The Two Nights Defence or Prussian Game. -4. Be7 the Hungarian Game, which are different in character and dont belong  to the italian game.

Firstly, i assume you mean move 3. Secondly, wrong again. The two knights, hungarian and giuoco are all variations of the italian game.

for example:

http://www.chess.com/opening/eco/C50_Italian_Game_Hungarian_Defense

whites third move, 3.Bc4 is what defines the italian game, after a response such as 3..Nf6 black has entered the italian game:two knights defence. All these responses are still a part of the italian game complex.

for a total begginer you shouldn't really take the evans ... you might want to try out first with spanish (ruy lopez) , you will learn key concepts of chess from the spanish. 1.e4 c5 is the sicilian defense ... no point telling you what to do since there's a lot to learn . search for the sicilian defense in youtube . 

black can answer 1.e4 with very good ways besides e5

1.e4 e6  (french defense )

1.e4 c6 (caro-kan )

1.e4 g6 (pirc defense )

1.e4  c5 (siclian )

and many others

focus only on the main lines for now and start to learn other stuff later .

ok, the english speaking chess world seems to dubb a whole lot of different openings under Italian. so then i am wrong when I point out, that the European heritage of the development of chess openings tells a different systematic order. Estrins book does not tell you anything about the TKD or the Hungarian, for example.

ECO Code 50 History

The Giuoco Piano is the oldest recorded opening. The Portuguese Damiano played it at the beginning of the 16th century and the Italian Greco played it at the beginning of the 17th century. The opening is also known as the Italian Game (Pinski 2005:5), although that name is also used to describe all games starting with 1.e4 e5 2.Nf3 Nc6 3.Bc4, regardless of Black's third move (Gufeld & Stetsko 1996:5). The Giuoco Piano was popular through the 19th century, but modern refinements in defensive play have led most chess masters towards openings like the Ruy Lopez that offer White greater chances for long term initiative.

And in the italian Wikipedia there is

La partita italiana è un'apertura nel gioco degli scacchi caratterizzata dalle mosse:

1. e4 e5
2. Cf3 Cc6
3. Ac4 Ac5
4. c3

Questa linea di gioco è nota da secoli: se ne parla in un trattato di Pedro Damiano del 1512, ed altre mosse di questa linea sono riportate in opere ancora più antiche. Fu riportata in auge da un grande scacchista italiano, Gioachino Greco, che la analizzò approfonditamente dando il suo nome ad una variante di questa apertura, la variante Greco.

All lines outside of 2 Knights Def are in here.