I reverted back to the original driver (ver 61.93) for my Nvidia GeForce FX 5200 (128MB) and it apparently cleared up the hanging and crashing issues I was having. I don't know if this helped, but after the driver install I left the color quality at 16 bit, changed my resoultion back to 1024X768, and (from the Nvidia control panel) changed the Image settings to High Performance, and left Antialiasing and Anisotropic settings set to application controlled. I played my first full game with 5 civs on a huge map without crashing, and with little noticable game lag. I did play the game with graphics set to HIGH. I do believe I need to set graphics to medium to improve performance, but this was a test run and it passed in my book. For those of you guys/gals running budget Nvidia cards like me (who desperately want to run the game) it is worth a try. I don't know what reverting your driver back will do for some of your other games and apps, so you might want to consider that first. I, like a few others, still believe a patch is needed to fix some of these issues. There is a similar thread where those running ATI cards with similar issues are reverting drivers to fix the crashes as well.
Thanks WarX
Pentium 4 2.8
1GB RAM
XP Pro SP 2
GeForce FX 5200 128MB

Pentium 4 2.8
1GB RAM
XP Pro SP 2
GeForce FX 5200 128MB