I now have both Portal games.  Haven't beaten the first one yet (currently at test chamber 15 with the energy pellet gun thing and the stupid buttons that DON'T GIVE ME ENOUGH FRIGGIN' TIME TO DO ANYTHING), but I tried Portal 2 anyway to see how well I could get it to run, since it's unfortunately more graphics-intensive and keeps telling me my video driver's out of date, and in fact I'm getting some choppy movement and stuttery audio that's pretty annoying.  

Not sure I can do anything about that yet, though.  Because here's the problem.  I'm still running Windows XP due to lack of money for Win7.  My graphics card does have an updated driver available... but not for XP, of course.  As far as I can tell, they don't even make XP drivers for this card anymore.  So I'm pretty much stuck with the outdated driver for now, I guess.

I'll do what I can with Portal 2, though.  Can't get enough Wheatley.  Such an adorable mechanical eyeball.