Please do this:
First create a permanent folder somewhere like in My Documents and name it Hijack This.
Now
Click here to download Hijack This. Download and save the file to the Hijack This folder you just created.
Click on Hijackthis.exe to launch the program.
Click the "Scan" button when the scan is finished the scan button will become "Save Log" click that and save the log.
The log should open in notepad. Click on "Edit > Select All" then click on "Edit > Copy" then Paste the log back here in a reply.
DO NOT have Hijack This fix anything yet. Most of what it finds will be harmless or even required. Someone here will be glad to advise you on what to fix.