I am running Windoze 98 with no probs. Unfortunately you cant create ANY NPCs

. 128 Megs is good , but more couldnt hurt. A GeForce 3 will work , but if you can afford it go for the GeForce 4 since you will get more use out of it before another upgrade is needed.
Just stay away from the GeForce 4 MX cards. All they are are GeForce 2 cards with a new chip in them. THat makes it kind of like droping a 2gig pent 4 chip into a motherboard built for a 250 hz Pent 1 chip.