Don't bother, I also tried playing around with similar stuff. My X1650 is newer than your card, still couldn't get it to work. I tried Ubuntu 8.x but the repositories no longer work. That means you can't even install stuff to be able to compile the kernel module.
I also tried Fedora 6 (probably). That partially worked, I was able to install the drivers, butdidn't get a decent picture on reboot. Might be fault of the old CRT though.
The question is: Would you really use an ancient kernel + distro just to be able to run proprietary drivers? I don't think it's worth it. You may be able to run a bit more games (Doom 3 specifically) but the card doesn't have any power to run it anyway. Other random linux games (like Chromium BSU) work fine on open source drivers. Even HL1/CS is playable.
CPU: AMD Phenom II X4 810 @ 3120MHz | RAM: Kingmax 2x2GB DDR2 800 @ 833MHz| MoBo: MSI K9A2 CF v1.0 (BIOS: 1.D)| GPU: Asus HD 6850 1024MB (DirectCu) @ 835/1135MHz | Display: L24FHD | PSU: PC Power & Cooling Silencer 750 Quad | OS: MS Windows 3.11 Pro x64