I like stating the obvious, you know. :-)

Have you got a Knoppix CD? If so, try it.

[link|http://www.knoppix.net/wiki/Hardware_FAQ#Q:_My_PS.2F2_mouse_doesn.27t_work.21|My PS/2 Mouse Won't Work!]

There may be similar tips on diagnosing video issues too, but nothing jumps out at me immediately.

I suspect that you either have a BIOS issue or (maybe and) you have some remnants of other Linux installs that are interacting in various ways. If it works fine with Knoppix (or any other live CD like [link|http://www.mepis.org/node/1462|Mepis] - the latest version is built on Ubuntu), then that probably indicates you don't have a BIOS or hardware problem. If it doesn't run fine from a live CD, well you have some more troubleshooting to do.

Hope you get it figured out. Problems like these can be very aggravating. :-(

Good luck!

Cheers,
Scott.