Wich game should I play?

The one that is fun

I will suggest steam roulette, it's actually pretty useful for me, but some weeks ago stopped working.

Receiver

Something you like to play

from what i see only fez is worth playing

Pong

Since i don't know which games you own i can't really say.And nope, i don't care about your steam profile :)
And you maybe should read the Steamgift FAQ.Giveaway means you give away a game.

FEZ, Blacklight: Retribution and Anomaly Warzone Earth are very good games.

A game I think.

Play the STALKER series with the complete mod.

Antichamber, easily played through in about 4-6 hrs total

Bit Trip Runner until you rage quit

Team fortress 2. Bit Trip Runner will make your rage GROOOOW!!!

Warframe, it takes a while to get into it though.

Sanctum
Tropico 3

KSP

Add non-steam game ---> Any virtual English grammar book :P