Hello all, I've been around a while and usually I can figure this stuff out myself but this problem has me stumped.
First, my setup
XP pro, SP3 32bit
Athlon 64x2, 2.93 gb ram
Firefox 4.0, eset smart security

Ok the best way to describe what is going on is with an example. Say I'm browsing and want to download a file, like malwarebytes. I click on the download link and the download box comes up but it's white, then firefox freezes, I click the X and I get the "program not responding" error. I end now and FF closes. I re-open FF and it restores my page/pages. I try to dl again and same thing.
FF browses fine, opens new tabs fine and runs fast.
Another example, offline. I have a .rar file to extract. I right click on the file and try and extract it with 7-zip or winrar. The extract box pops up and when I click ok it turns white and freezes. I click on the X and I get "program not responding".
Those are a couple examples, it does it with other proggy's to.
Also, my outlook express won't open. It acts like it's going to then turns all white and yes you guessed it, I hit the X and I get "program not responding".
I have searched for hours to try and solve this one but to no avail. What could be going on??

I have run malwarebytes scans, eset scans etc and it turns up nothing. I haven't installed anything new.

Oh yeah I forgot. I can't open IE either. Even when I try windows update, a white box pops up and "program not responding".

Any and all help will be GREATLY appreciated, thank you!1.Did it WORK before with the current softwares installed or anything added that causes the issue?
2.Have you tried running in safemode with networking and scanning with Malwarebytes or Antispyware?
Make sure they are updated before performing a complete scan.
3.If you have any external DEVICES installed such as memory card readers, try removing it from the PC.
4. Try disabling some features(Antivirus, Antispyware,Firewall, Antispam) from ESET and try downloading again or if you are keeping a software installer of ESET smart security, try uninstalling it and use another Antivirus such as Avira or Avast. You could also use Windows firewall instead and try updating your OS and drivers.
Thank you for the reply Jason. 
It worked fine before, I haven't added anything.  I ran scans in safe mode with MB and Superantispyware, both updated but were clean.
No memory card readers, just an external HDD and burner and even with those disconnected, same problems.
I disabled Eset and still same issues.  I've used Eset for years, it's my favorite of them all and I've never had problems and I don't SEE how it could be causing this problem. 
I can't update my OS manually because IE won't open.  All drivers are up to date. 
Any other suggestions anyone?What happens in safe mode?Do you have any description or details of errors or messages aside from program not responding?
Quote

IE won't open

What happens in safe mode?

1.Did it work before with the current softwares installed or anything added that causes the issue?
2.Have you tried running in safemode with networking and scanning with Malwarebytes or Antispyware?
Make sure they are updated before performing a complete scan.
3.If you have any external devices installed such as memory card readers, try removing it from the PC.
4. Try disabling some features(Antivirus, Antispyware,Firewall, Antispam) from ESET and try downloading again or if you are keeping a software installer of ESET smart security, try uninstalling it and use another Antivirus such as Avira or Avast. You could also use Windows firewall instead and try updating your OS and drivers.

I had a similar problem, on XP using IE, How I first noticed was my desktop shortcuts wouldn't open programs then using Start/All Programs that once I clicked on any prog or accessory that it wouldnt open (including Sys Recovery and SysInf, any application repair) and the icons would turn white. Then I couldnt DL anything, would go to 98% then box says DL failed. If this is anything like problems you are having you try to open a program in folders a box says open with: choice of programs on your comp or ask if web help will open it. And web help page opens same window everytime where no links can be DL'd) Neither works. when I started looking in my folders, all my .exe .dll .ini .bat any Media Device App icons would be white and say in properties Unknown Application and trying to open it, it would say something about it has no file association, meaning it couldnt be opened by any device or driver.
IF you see those desktop icons, all the icons in all programs changing to the white icons, the icons in Control Panel stay same icon, but dont open a 2nd time. and nothing Downloads. It's already too late, UNLESS your task manager will open. then maybe you can associate each device with its program path. But if it opens, Do not close it, any program you can open, dont close it till you've done all you could with it.

I had roundabout ways to open Media Players, they can only be opened by having a song or vid "Open with" your player.

I saw so many people describe these symptoms on help sites and every tech gave bad advice, if you cant open or DL anything they'd say DL this or Run this Virus removal, or Malicious software remover. I hope you dont have it. Only difference is my IE still worked just fine.  I did get a Dl of a virus scan to scan and print out results. Called Panda Active Scan, the scan is free and thorough. I have Trojan Virus at 2 or 3 locations, all the executional devices had a virus caledl Adware Virus. The 68 threats and problems were printed on 5 pages. Its a free scan, the removal tool you pay for, but that cant be completely downloaded either, the scan wasnt either.
I dont know if is virus you have, but check the signs of white icons, if it starts,  disconnect from your modem, you were hijacked. Make sure you use different name for Administrator. Your only chance is offline, Hope you have made back ups or have XP disk, they stopped selling.  If not, you can save personal files onto disks, then with disk, Full Recovery.