The 81.98 XP drivers work in Vista 32bit, so they may work on 7 as well. You're still probably not going to get full features, and Aero is definitely out, but you might at least be able to extend the desktop.
The better option, though, is just to look for a newer card. Any DX9 card should work fine, that would include the Radeon 9500 or above, or any Nvidia FX series or newer. You can surely find something suitable for $10-20 either in the classifieds here or on eBay, and IMO it'd be worth that much just to avoid the hassles with the GF4. I mean, it's a good card, but it's just not a Vista/7 card.
+1 on the advice to upgrade. I still use a ti4600 in one machine, and my brother still uses a ti4200 in his only PC. However, both of those are used under XP. For Vista or Windows 7, you will do well to use something more current, even if it isn't more powerful.