Here is an interesting link from the Washington Post, describing how to access Administrator privileges on your Windows Vista or Windows 7 machine:
http://www.washingtonpost.com/wp-dyn/content/article/2010/10/11/AR2010101103329.html?wpisrc=nl_tech
It is interesting that the recommended way to solve a lost password issue on a Windows box is to access it from a Linux system! By the way, I have used the same technique to root out viruses on my dual boot system- back when I still let the Windows sector access the Internet...I also use the Linux system to check for viruses on my thumb drives- they are a whole lot easier to find and kill with Linux...
Good Answers: