help again with xp

i just got xp on my computer but it still has the win2000 professional how do i totally remove that is there a easy way to do it, and second when ever my comp on i get these pop-ups for microsoft program but the popup blocker doesn't catch them how can i get rid of those.

I don't understand what your first problem is, but I do comprehend the second part.
Go to the download.com and check out their tools to get rid of adware which may be causing those pop-ups. If none of those tools work, I will give you steps on how to use that HiJack This program.