This is an odd one, especially in Linux. I used to have Mandrake on my computer back before they merged with Conectiva to become Mandriva, and every once in a while, I'd run into something that would cause Mandrake to freeze up more solid than a block of ice. Mind you, I was fairly new to Linux at the time, so it's entirely possible that it may have just been that it was KDE freezing up and not Mandrake itself, who knows?
But anyway, I always found Mandrake/Mandriva to be real flaky when it came to stability. It's been about a year and a half since I got rid of it and switched to MEPIS and later my current distro, which is PCLinuxOS 2007. Some of the problems I had with Mandrake that I can recall include it freezing up when I tried to start Rosegarden, at which point I went for the reset button on the case and promptly uninstalled Rosegarden when I got logged back in.
I also remember some KDE interface behavior weirdness when I'd boot up some live CD's, and I didn't even try to install them, either. I got to where I had enough of all that nonsense in June of 2006 and shopped around for another distro, and at the time, MEPIS seemed to fill my needs best, but this past summer, I found myself even more impressed by the current version of PCLinuxOS and switched to that.
Therefore, quite frankly, I would change distros if I were thee. My own experience with Mandrake/Mandriva, while it was an enjoyable one overall, was also haunted by incidents such as the one you describe. But all is not lost, though -- PCLinuxOS 2007 is based on Mandrake/Mandriva, and, in fact, in the way everything is arranged, very closely resembles Mandriva. It even has all the Mandriva tools on it, such as diskdrake, userdrake, drakconf, and the like, leaving no room for doubt what it's based on, and as such, I think PCLinuxOS 2007 is a distro I think you'll feel right at home with.
I've been using PCLinuxOS on my computer for the last four months, and I've never once seen it crash. It's a distro I swear by, and in fact, I find it to be an overall better distro than Ubuntu, and I'm not just saying that just because I prefer KDE over GNOME, either. If you have a high speed connection, just head on over to www.PCLinuxOS.com
and grab yourself a copy.
Good luck and let me know how this goes, OK?
Fred in St. Louis