I have used windows XP for more than 2 years and used Vista over an year, but I started to try out other operating systems in order to replace Windows, Mac OS X is my best liking but i would need to buy a whole new hardware so started trying out Linux. I tried out Fedora and Ubuntu, after using Ubuntu for 6 months running parallel with Vista i have found it so good that now i have completely removed Vista of my laptop and running only Ubuntu (8.10). The biggest reason that i dumped windows is the system crashes. With Ubuntu i have no such worries. The only problem i have with Linux is Vendor/Hardware support. I hope that more and more companies will start making drivers and important software available for linux and as soon as possible.

Have you tried Windows 7? It's a lot better in my opinion than Vista.

Yes, I think that 7 is better than Vista, only in that it is more stable, meaning that is doesn't get slow as fast. Ubuntu never gets slow. I have a Pentium Dual-Core and in Linux, it runs as fast as my friend's Quad core in Windoze.
Linux just works.