If you are registered, you get access to the members only section, can participate in the buy & sell second hand forum and last but not least you can reserve your preferred username before someone else takes it.
I'm running Vista also. My guess is, you don't know where to go to uninstall any software rather than this being a Studio specific problem.
If so, go to control panel. In the upper left, click on the link for "classic view", if you're not already in that mode. personally, I find the classic view easier than the newer view that Vista came out with. Once in classic view, click on the "Programs and Features" icon. Once the window populates with all the installed programs, hilight the one in question and click "uninstall" near the top of the window.
It's much like it was under XP, just rearranged a bit by someone who didn't like the furniture where it was.