My browser doesn't load pages correctly

[Scoobydb]

I’m having severe problems with my browser. I get the same issues with IE, Chrome and Firefox. Pages either don’t load or load very slowly and the small revolving circle on the tab showing page loading is underway keeps revolving, even after the page is loaded (on Chrome this circle sometimes revolves backwards). Often (but not always) I can stop the page loading and hit refresh and the page loads instantly. I normally run a wireless router but I’ve tried a wired modem with same result. I don’t think it’s my network as I’ve tried a different PC at the same time and that works fine. It sounds like a virus but I’ve run AVG, Spybot, Advanced System Care and numerous other scans and blockers and my system appears clean. I’ve tried de-fragging and removing programs no longer used. I’ve removed and re-installed my browser. I also notice my CP usage runs at 100% some of the time. It also takes an age to power down. All this started suddenly about 1 month ago and I’ve searched the net and there have been 1 or 2 similar problems but none of the fixes work.
I run XP Pro and my broadband connection is with Talktalk and speed tests show download at 6mb and upload at 0.6mb.
I’m at the point of re-formatting and loading everything again but don’t want to do that if its hardware related. The other option is to buy a new PC but that’s a bit drastic.
I’m at my wits end so any help gratefully received.

[patio]

Do you have Automatic Updates running in the background ? ?

[Scoobydb]

Thanks Patio,
I have auto updates turned on but not to install until I'm notified and agree.

[patio]

DLoad and install Process Explorer...
When you see slowdowns...open it up and see what's running in the background.
I still think it's a connection issue...

[Scoobydb]

I've downloaded Process Explorer but not quite sure how to interpret the results. The attached file was run when my browser wouldn't load a page but CPU usage was only between 6% and 15%. Can you see any clues as to the problem.
Very grateful for your help.

[Saving space, attachment deleted by admin]

[patio]

If this is a Home machine you can disable the on demand AVG scanner and the Network scanner services...

[Scoobydb]

It is a home machine and I'll try as you suggest but I think I've always had the scanners enabled.

[Broni]

Go Start>Run (Start Search in Vista), type in:
msconfig
Click OK (hit Enter in Vista).

Click on Startup tab.
Click Disable all
IMPORTANT! In case of laptop, make sure, you do NOT disable any keyboard, or touchpad entries.

Click Services tab.
Put checkmark in Hide all Microsoft services
Click Disable all.

Click OK.
Restart computer in Normal Mode.

NOTE. If you use different firewall, than Windows firewall, turn Windows firewall on, just for this test, since your regular firewall won't be running.
If you use Windows firewall, you're fine.

Same problem?

[Scoobydb]

Thanks Broni,
I can't say for sure until I've run my system for a while but following your advice seems to have speeded things up. The pages now seem to load and the revolving circle (what do you call that thing) stops now. However, I guess I can't run my PC with all these things disabled so what is the next step.

[Broni]

Re-enable everything, you disabled.
Uninstall AVG, using AVG Remover: http://www.avg.com/us-en/download-tools
Restart computer and report back, how things are.

[Scoobydb]

Well done Broni, this produced the same result as disabling everything so it's possible AVG was the root of the problems. As all of AVG has now been removed can I simply download and re-install again or do I have to use another anti virus prog. If so do you have any suggestions.
Thanks very much.

[patio]

Avast Home is Free and a good alternative...

[Scoobydb]

Thanks Broni,
I've now downloaded and set up Avast.
I'll leave the post open for a few days to see if the problem has gone away. Any problems I'll be back on.
Thanks very much for your help.
Regards

[Broni]

Cool
Make sure to run AVG Remover: http://www.avg.com/us-en/download-tools since AVG surely gave you some leftovers, if you simply used Add\Remove to uninstall it.

[Scoobydb]

Thanks Broni,
I ran AVG remover as you suggested