When I try to run the program from tutorial #1 and #2 (both the compiled and the .exe version from the NeHe:s webpage) a messagebox pops up and asks me whether I wan't to use fullscreen of window mode. If I choose window it seems to crash almost instantly, but I if choose fullscreen mode it changes screen size and then crashes (sometimes it doesn't even return to my old screensettings). By the way I'm running Windows XP Home Edition and have a ATi Radeon 9500 Pro / 9700. Anybody knows what's wrong?

it looks like your unable to initialize opengl, it could be any number of things.
First get the latest drivers for the graphics card, and anything else for that matter.
secondly, check if any opengl based games(like quake3 or doom 3) do the same.
thirdly, download other tutorials and games form the site and see if they work.
Finaly place a pipebomb inside of the computer en blow it up. j/k

yeah what lc_overlord said. and also there are some ati driver problems for gl i heard. better is to reinstall your graphics card drivers (get the latest ones)...

yes, installing the lastest Catalyst drivers (V6.1 from https://support.ati.com/ics/support/KBAnswer.asp?questionID=640) worked =)

THANKS!!!

I now have another problem, this time with tutorial #7... (this goes for both fullscreen and window mode) when I press the up keyboard button the cube is rotated so fast that it almost looks like a sphere and after a while the videocard crashes (the window locks seconds later the whole screen locks, and the computer stops respond, last the screen gets black).

I've tried to contect ATi (and even sent a crash report to them) but they havn't answered.

Anybody knows what might be wrong and how to fix it or avoid it?

Hrm. Well, my suggestion you might not like, but I'd suggest going with nVidia. I've got a really old nVidia card that can barely do hardly much of anything and it has none of the problems you speak of. So I'd suggest nVidia