Albatross,
For a new video card, you shouldn't have a problem. The Dell 4300-series machines are really easy to get inside of, and your computer has an AGP port. This is a special slot on the motherboard that allows you to use many of the newer higher-end video cards. Depending on how much money you want to spend, I reccommend the ATI Radeon 9000 Pro 128 MB card (I know somebody else said they didn't like it, but I've had no issues with it). You can pick one up for about $120 dollars, and it really makes life sweet. If you want to go a little lower, you could get an Nvidia GeForce MX440SE card for <$100. Beware...it's not a true "Geforce" graphics processing unit, but it performs pretty well. This will definately speed up your game. And remember, get all those little programs in the task bar out of there! FS2002 doesn't like other software running in the background!!!