NO way am I smarter than ANYBODY Dom. I am sorry that I seemed upset, I was a bit. It is so frustrating to see somebody with a good computer take the chance of having it "nuked" by not having an anti-virus and also then putting others at risk.
Let's go back to the beginning OK?

Avast is a bit more of a resource user than Avira, though much less than other programs available for pay. One reason I was pleased that you chose that is that it DOES have email scanning, while Avira Free does not.

Let's get things cleaned up first, then we can talk about how to speed things up a bit.
Run HJT again and put check marks next to the following entries:

O2 - BHO: (no name) - {02478D38-C3F9-4efb-9B51-7695ECA05670} - (no file)
O2 - BHO: WormRadar.com IESiteBlocker.NavFilter - {3CA2F312-6F6E-4B53-A66E-4E65E497C8C0} - C:\Program Files\AVG\AVG8\avgssie.dll (file missing)
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O18 - Protocol: bwfile-8876480 - {9462A756-7B47-47BC-8C80-C34B9B80B32B} - C:\Program Files\Logitech\Desktop Messenger\8876480\Program\GAPlugProtocol-8876480.dll

When you have the check marks in place then click the Fix Checked button. Exit HJT.
Reboot the computer.

Next thing to check is your Firefox. Make sure it is totally closed down. Go to Start, Programs, Firefox and choose to open it in Safe Mode. Now this is the browser itself safe mode not the entire computer. What this does is open Firefox without all the add-ins and plug-ins turned on, just the basic browser itself. If the opening speeds up then the problem lies with one of those extras in it that is slowing it down. To determine which one is to re-enable them one at a time. You should soon find which one is slowing things down. Also, what version of Firefox are you running?
Let me know if opening Firefox in Safe Mode is any speedier.
After that we will work on unnecessary start up programs and services.
Judy