I guess you just have to click the icon without typing in a password. If so, this is exactly what happens when you have had the .NET framework installed, which is required for optimal use of Vegas 5 and it's scripting capabilities. No harm whatsoever is made to your computer.
To get rid of the icon-clicking just go into the Win XP "Control Panel" and open "User Accounts" (I'm using XP Swedish so I'm not 100% sure of the name). There you'll find a new ASP.NET account. Click on it and then choose to delete it. Restart your 'puter and it should log in immediately without the icon click thing.
Tommy,
You hit right on the head on both counts. I had just reinstalled framework 1.1 and deleting that user account took care of the problem.
Thank you sir,
Barry