Unity fails to load

okay, 2 days again I downloaded the unity editor, well when i first ran it it came up about registration, i registered it said it went fine, it then asked what i would like to use, so i went and selected everything i could figuring just to mess around and get use to the editor. well after this, the program closed. the process no longer running.

So i double clicked the unity shortcut, it shows the splash screen with the soldier holding his gun. then it closes, again the process is gone from the list. ?.? i restarted my pc, uninstalled the program, restarted again, reinstalled and then restarted again. launching the program again, i get the splash screen and it closes again, with the reinstall i dont see the registration stuff or the choosing menu i got before ?.? please help me. I've submitted 2 bug reports on this issue.

How do i get this thing to actually work since it wont run? btw, the mono editor runs but not unity itself. ?.?

I'm running windows xp pro 32 bit sp3, with 4 gigs of ram, quad core 3.0 cpu and a nvidia 295 graphics card.