IE7 sometimes hangs until task bar brought up

Occasionally when going to any random website IE nearly hangs. The progress bar on the bottom just stops increasing or slows progress to a 5 minute crawl. Eventually it gets there but painstakingly later. When this happens I've noticed if I pull the mouse to the bottom to bring up the taskbar, it usually gets out of it and shows normal progress or the site will come up right away (if its been awhile). It's like it needed that interrupt to get itself out of where ever it is stuck. This phenomenon has been going on for years through multiple IE versions and pc hardware (although I've always had dialup). Any ideas?

I'm running IE7 on XP Pro SP3 on a eMachines 2.7ghz desktop with 1GB ram on dialup. I have the latest Windows updates, run Norton AV, and checked for latest malware, spyware, adware, viruses, drivers, cleaned registry, eliminated all unnecessary software and processes, etc.

 

Not tried updating to IE8?
Do a spyware/malware scan?

 

I tryed IE8 but its way slower than IE7 in all areas so I went back. Every new version always is way more graphic intensive and has dozens of new options/stuff that must be loaded which makes it unusable for us dialup guys. I already have to wait an average of around 20-30 seconds for any website now at midnight (daytime is hopeless). IE8 went into minutes. And this is trying it both with and without cookies, ad blocking, host file updating, reduced processes and software.

I'm not familiar with Add-ons. Just what exactly are they? Are they always loaded and when do they run? Why might they cause problems and do they slow things down? Looking at the list they look pretty important to have, like apps won't run right w/o them. It also appears you have to disable/enable them 1 at a time and so you'd have to write down the status of every one to know how to put them back.