sorry to say but you are infected and there is no time to waste...
get this
http://free.antivirus.com/hijackthis/
dl the excutable version
run it
choose "Do a Scan and Save a log file"
after the scan is done please post it here ( a blocknote page will open , this is the log file that contain only the information about what is running , what start when you start your comp , and what is using your ie.
after that I will tell you what to do but I need that log file to continu...
ty