1. You should uninstall either Norton or AVG. You should only have one antivirus or they may cause problems with each other.
2. If you are "constantly plagued by Adaware and viruses", then its likely you either have something your antivirus isnt picking up that is re-installing nasties, or you frequently use P2P programs, or visit "rouge" websites, in which case simply stopping that type of activity would help.
3. Antivirus programs are in no way intelligent, its to be expected that some viruses will get past them.
4. You should be fine using either Norton or AVG, just make sure you use one or the other, not both.
My suggestions:
Uninstall either Norton or AVG(leave one of them though).
Update your antivirus definitions and run a full system scan, then run some online scans too.
If you have a connection faster than dialup then think about installing a firewall. You can download a free firewall from the link below:
http://www.zonelabs.com/store/conten...ulist_download
Help pervent adware/spyware form infecting your system in the first place by installing the below programs:
SpywareBlaster
http://www.javacoolsoftware.com/spywareblaster.html
SpywareBlaster can prevent spyware from installing itself on your computer. It does require updating every now and again, but it's rather easy to operate. Just install, run, update, click "Protect," and you're done. Update once every month or so.
IE-SPYAD
https://netfiles.uiuc.edu/ehowes/www/resource.htm
IE-SPYAD places over 4,000 known evil sites into the Restricted Sites zone in Internet Explorer so they cant execute ActiveX, Java, or place cookies on your machine.
Aslo go to Windows update site and install all available critical updates.