I use Kubuntu, and I love it. My battery life is about %50 more than my XP install and I have access to thousands of programs that on windows I could only get illicitly and would have to torrent. Whenever I'm bored (which is rare anymore) I browse through Synaptics, the package manager, and look for interesting programs to install. You don't have to worry about the registry bloat that installing too many programs on windows causes, as linux has no registry

. Also, no spyware/adware in programs in the Ubuntu Repositories, just loads and loads of programs to try out, experiment with, and remove if you don't like. Believe me when I tell you that if there is some arcane little use that you think may conceivably be built into a program, chances are someone has, and released it open source.
I already have used a live cd of ubntu a few months back. What sort of software are you talking about?