Hi, I noticed another thread about somone having problems with vista loading then a blank screen - no start menu, toolbar or icons. I tried the reply of getting up task manager, new task then typing "explorer" in, it fixed it! What I want to now is, What was wrong? Why is it doing it?

That's quite hard to say. There are a lot of reasons, that may cause explorer to not get loaded. You may find details in the event log.

I recently downloaded AVG, could that be it?

Depending on the settings of AVG. I did not really know AVG, because I'm using another antivirus, antispyware and firewall tool. But if you configure any of that tools to hard, this may cause such problems. Especially application firewalls can cause this, if some windows exe files are not allowed to start. Therefore, eventlog and the firewall log are alway worth to look for.