That's strange, Windows should not be nearly that unstable. It's far from perfect, but I've kept Windows 9x boxes running flawless for days to weeks, and NT4 or 2K systems can easily stay up for months. Properly configured systems with decent drivers and software are usually fairly stable.
Linux itself is stable, but a lot of the applications available for it are very buggy. I haven't seen an instance where the entire OS goes down because of a program crash, but I have crashed out of X numerous times, which is effectively the same thing.
Just be happy we aren't stuck with MacOS. That archaic piece of trash makes even Windows 9x look good.