Obviously, we can live without any games at all. But then, that makes for a dull conversation. Frankly, there's probably somewhere like 50 games, that if I could only have 10 or 15 in that whole list, I'd be happy for a good long while. It helps that since I'm going to college right now, I don't have the hardware for decent PC gaming or the time for much gaming, and coming from a two sibling house meant I had to leave all but one home console back home. I've got a DS, PSP, 3DS, and the console I took was our old NES, of which 15 months after moving into this place, I finally got a TV to use it with last night.
As far as what I still play, tons. I'd play more if the equipment worked better and there was less static when trying to use older systems on the 50 inch. I've got NES games that I pull out from time to time, gameboy games that I pull out. Most of my favorite RPG games are on PS1 and PS2, and I still play N64 and xbox when in the mood. Out of maybe 400 games around the house, there's probably about 4 dozen that I haven't touched in the last six years (not including games I never played, either due to lack of interest [except my brother] or games that would never run [Specifically, some xbox titles that I couldn't get to work]. And some of those that I haven't touched are due to the fact that 360 isn't fully backwards compatible. I also don't care for sports games), so yeah, I still do like to plug in an old console and go back to pixels and rough polygons.