unwiseowl,
I call 400Mhz the fence. You could go either way with 400Mhz, but less I would not recommend WinXP at all. Since you only have 96Mb of RAM, your best bet is Win98SE.
The only way you would be able to run a DVD Drive would be with a Hardware Decoder.
It might be time to think about upgrading you entire computer. (Depending on what you use your computer for.)
Take Care,
Richard