double clicking icons causes computer freeze

I have two problems.

1.) When I switch on my PC, the internet dial up connection box appears automatically. Why?

2.) My start button as well as Launch outlook button and show desktop button work, but as soon as i double click on my documents or any other icon on my desktop. The window opens but is completely blank. Then no other buttons work, not even the start button.

My problem started after I downloaded Hotbar.com.

HELP!!