Internet explorer hanging

[#1]

I'm running Windows XP, just reformatted drive, installed all updates, AVG 8.5 free.  When i clickk the big E to go to my browser IE-8 everything seems ok for the first 15 minutes or so.  If I then let it rest for ten to fifteen minutes and then resume browsing I can't get back onto any websites at all. I use Plus net as my homepage but even that won't come up, the green dots on the progress bar count up to 3 or 4 then hang forever hence no web page. If I then do a restart or re boot, every thing is back to normal again for another 15 minutes or so, then no internet or web pages again.  I must state that before i updated to Internet explorer 8 I was on IE 7 and these symptoms were just the same on 7.  I also have a laptop on Vista Home, with IE8 and there is no problems with this.  Am using plusnets free Thomson Router.
Any help will be greatly appreciated .
Percy.

[#2]

Install Firefox and use it.

[#3]

whats event viewer logging when IE is playing up?

[#4]

When it starts playing up, there are no entries in the events log for internet explorer.
I also tried firefox but although it worked I couldn't find any way of editing my website with microsoft frontpage like i can in internet explorer.

[#5]

When it dies again open a cmd windows ie start run type cmd then in the window type ping www.plus.net and see if you get a response report back. If it doesnt respond then its your connection not IE thats the problem. Dont understand why using firefox has anything to do with editing your website explain?

[#6]

Hello Samura,  when It hangs and I use cmd and ping www.plus.net I get a full report back.  during the time its misbehaving i can still get yahoo or msn messengers to work perfectly.
regarding editing my website:- I get the web page up on screen and go into file-edit with microsoft frontpage.. in Internet Explorer... but when using Firefox and i go into file there is no visible "edit with Microsoft Frontpage" to be seen so i don't know where to go from there, i've never used Firefox before this, so i'm not conversant with it.  It would seem plausable
that as the messengers work ok then the connection would be ok too.
Percy

[#7]

If you open frontpage directly and look in recant documents you webpage should be there. Its just a matter of working out were your website is on your hd and then opening it in frontpage directly. If you open you site choose save as as this will then show you were its putting the files
If you can ping ok and use messenger then the pc hasnt dropped the connection so the problem is IE. On your menu normally under start\accessories\system tools you should have a IE with no addons. Instead of running normal IE try that and see if it work ok. If it does then the problem is an IE addon its just a matter of finding the one giving the problem.
Does Firefox run ok?
Have you got google toolbar installed in IE as this often give the problem you describe if you have try uninstalling it