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 it and click "Save". Save it to the Hijack This folder you just created.
Click on Hijackthis.exe to launch the program. Click on the
Do a system scan and save a logfile button. It will scan and then ask you to save the log. Click "Save" to save the log file and then the log will 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.