Question about rook placement/attack

Hi

I am reviewing one of my games and I was in the below position, i am white.

From this position i moved the rook Rgxf7, but a better move was Rfxf7, which is shown below. 

I was wondering why this move is the best one?

Thank you

My english is crap but I'll try,ok so basically when you take with  Rgxf7 you double the rooks vertically while you are still winning there is no real threat(s) that you've created with that move  but when you take with Rfxf7 you double up horizontally on the 7th rank(which is generally really strong) and you have many threats such as Rc7+ and picking up the b pawn, moreover you can also threaten mate using the two rooks forcing black to give up even more material and eventually win an easy game. Hope this helps : ) 

Oh Yeah that makes sense, i remember now that rooks on the 7th rank are really strong. Thank you so much

By moving as shown on second board you are as well ensuring a possible attack on King. 

There's nothing wrong with the move you played. In fact, it's probably the clearest win.

A computer will prefer the mathematically shortest win, or the move that gives the highest evaluation... regardless of how complicated the variation.

But any sensible Human player, once they are a Rook ahead, will prefer the move that reduces the opponent's counter-chances and makes the win as clear and simple as possible.

So I would have played Rgf7, just like you did, in order to follow up with Rf8+ exchanging off Black's last Rook. This reduces the position to a very simple win, and prevents Black from finding any counter-play to confuse the winning process.