The first one is Inotia, the second is Social Soccer and the last is GTA.
I downloaded and saved them on your pendrive, you can play (it) whenever you want.
[perhaps you can play them would do here, you downloaded three, but I preffer to think that "you can play it" is accurate, because you will play just one.
Well, I leave the ball on the experts court now.]
If you want, [or "you wishing,/if you wish," but always with commas immediatelly afterwards.]
If you want, after finishing my homework I can search and download more games for you to play. [or " ...after finishing my homework I can search and download more games." Since the remaining doesn´t adds much to the understanding of the text.]
One wouldn´t download games and not to play them, or at least it´s not the intention.
Normally, people pay me for doing this (or - doing that); however as you are my friend, I just want you to thank me.
[To me, but this is just a instintictive thing, "however as you are my friend, you can just say thanks". A bit more informal. Your way is fine, though, it´s not a matter of wrong or right, just of style or liking, maybe.]
So, you can tell me later which game (or "wich one") you liked most. [notice the inversion "liked most."]
The best (one) in my opinion is Social Soccer. Enjoy the games (them). I hope you answer (my email/my message/me). OR
I am waiting your answer/reply (reply is a bit of British English, whereas "answer" is more of American English.)
Hope it helps.
And waiting for any fine-tuning, comments, editing, emends and suggestions by others participants of the Forum.
See you again.
And while at it, your writing skills are going from strenght to strenght by the day, Ancrispa. Congrats!