Shuttle SP35P2V2 small form factor pc from a couple of years ago
Your computer takes PCIe, yes?
In his first
post dave says it's a system from a couple of years ago. The Rage XL is a videocard from the early 21st century. The ATI Rage card is a PCI card, not a PCIe card. There's a big difference between them. So, if dave uses an old/ancient PCI card and he mentions that his system from a few years ago, the answer to buy a PCIe card is not a good advice. Best is that dave checks his system for any other ports/slots. If his system only has PCI, there's not much to do beside to buy a newer Nvidia PCI card...
1) Go with either an old version of LM and/or an old version of xorg
Not a good option. An older version of Mint is no longer maintained and supported. So after installing you won't get any updates whatsoever. Using an old xorg could break your system.
2) Buy a new computer
That's an option if you have money for it... But that's your decision, not mine.
3) Buy a new video card
If you can find a PCI videocard which is newer than your ATI Rage XL...
Pick a nice budget card or three, then do a search on them including terms like linux, mint, and ubuntu.
First find out which card is still supported and is a PCI card. Then find the right card for the right price. That's the way to do it.