PSX: 29
PS2: 75
PSP: 11
PS3: 46ish (tough to remember all of my PSN games without looking)
Gamecube: 11
NES: 3
SNES: 19 (I thought this was higher. I'm wondering if all of them aren't sitting on my shelf right now)
N64: 24
Dreamcast: 7
DS: 10 (most are my wife's but smurf it, I'm counting them)
GBA: 10
Game Boy: 10
PC: 76

That's more or less all of them. So that puts me at 331 games in total. Not too bad I suppose. Obviously I'm not going to list everything individually, and as far as beating them, I'm not actually too bad. When I was actually attempting to track this on backloggery.com (before I got too lazy to keep updating it) I was in the 70-80% completion range on all of my platforms. So that's anywhere from 231-264 of them beaten. Not too shabby.