Thats a tough one. Since my brain cannot handle the thought of playing games on a 15 inch screen anymore, I'm going to stab into the desktop PC.
The 220 wasn't built to game and is suited for HTPC's. At that resolution with mid or low game settings and your needs (and depending upon what games you play), you sound like a GT250
It will give you an entry level (yet sufficient) performance where-as a 220 and 240 should not be considered for any type of current gaming.