you need to remove all your background programs that are currently running.
check out this page here on how to do that:
After you do that you should run a full scan using two programs, Adaware and Spybot. They are very strait forward programs, update completely and run.
After that make sure you restart, then make sure you have no remnants of any anti virus software, come here and ask us to be sure if you are not.
then install a program called AVG antivirus, update and do a full scan.
then get an internet browsing program called mozilla firefox and use that as your default internet browser.
All of the above programs can be found at download.com.
do all that then come back, and further removal strategies will have to be taken. but good luck and remember computer repair is only a few clicks away