Infected by Win32:TratBHO malware

I am hoping someone can help me. My computer has Avast 4 home edition and it keeps finding a Win32:tratBHO infection. I delete it and then it comes back over and over again.

I am not very good with computers so I am hoping someone will walk me through the fix.

Any help would be much appreciated.

John

There are a number of topics relating to this trojan (forum search}, this is just one, http://forum.avast.com/index.php?topic=33485.0.

See if you can follow the information posted.