[Wine] Napster: Success! Almost. Guests group problem

[smheath]

So I was somehow able to successfully install Internet Explorer 6, Windows Media Player 10, and even Napster 4.5. Napster kept saying that WMP 10 was not installed, but eventually I was able to make the error go away (I'm not really sure how). But now when I start Napster I'm getting the following message:

"You cannot play protected content if you are part of the Guests group. Please remove your user account from the Guests group and then restart Napster. Contact your system administrator if you need assistance."

And then I get a runtime error. So... how do I remove myself from the Guests group? I think I may have found the key to success with Napster!