Man, I am I ever glad to be the sole owner of my computer. I mean, it IS vista, but I've hacked everything from the system32 files, to the registry, to even the start-up/log-on screens. Modified start-up programs, took off tiny things like the arrows on shortcuts, and more. Have experimented with animated desktops, and more.
A nice thing about being the sole owner is that you can change everything to YOUR preferences and no one else could care! I don't use linux just because so many programs still rely on windows stuff, and the games for PC that you can buy probably wouldn't work... Despite its flaws, I really don't mind Vista (not sure if I will ever upgrade to 7 when it comes out. I've seen the prices, and I've seen the feature list, and I'm pretty fine with my current OS).
Being admin is great, but it makes little difference to me, being the sole user. I have since disabled UAC (seriously, It hasn't done anything good for me. COMODO will handle everything [lots of work to tell it how to do things]).