That practically takes an expert to do on its own :/ But yeah get rid of Norton and pick up a good antivirus. AVG Free Edition is really good for a free antivirus, you can grab it over at
http://free.grisoft.com, just keep insisting you're sure you want the free one till the site finally coughs it up, which is a mini-game on its own (for people that make a free antivirus they are sure reluctant to let you download it).
You may have a tough time removing Norton if you're under the influence of malware currently, don't be surprised if the uninstaller fails to work. Try running an Ad-Aware scan first to get rid of it before you do anything else, then download and install AVG then remove norton if you can get things to work in that order so you don't have any gaps in protection. Also, make sure Windows is up to date, a lot of these things work on exploits that get fixed in updates.