TT girl I really don't know what to tell you to search for. Try searching for the file types you have been downloading.

It seems more and more to me like you downloaded a virus or the computer has been infested with spyware.

search the forums for adaware, spybot, and anit-virus programs.
You will find several posts on these with links. Most are free or have trial versions. you can also google these on the internet.