My son's computer had the ISearch Trojan which Norton Antivirus chose to 'Ignore" so he when into explorer and into System32 files and saw one that had a icon that looked like a trojan so he deleted it. Now several IE 6.0 files are missing and IE will not open (System file opens instead to let you search for IE.) He's got WinXP Home w/SP2. Is there an easy way to reinstall IE with SP2 without doing a total XP reinstall or massive edits to the registry? Microsoft site only tells you how to do it with XP or XP SP1 not with SP2. The version with SP2 involves tons of edits to the registry. Any help will be greatly appreciated.

Try the suggestions listed here:
Repair Internet Explorer 6 for Windows XP

Also you might want to install and run Lavasoft Adaware to make sure there is not some spyware on there. This is not quite like an antivirus, it does not run in the backround, it only scans your computer when you tell it to.

SpywareBlaster is also a good tool to keep the spyware off of there. SpywareBlaster does not take up any system Resources. It basically just adds a lot of the known bad sites to your 'blocked' list so that if a popup originates from there and trys to install some spyware it is blocked. It's a very beneficial tool.

Both are linked in this thread. Or you can simply search google for "Lavasoft Adaware" and "SpywareBlaster"

We've already run, Ad-Aware, Spybot Search & Destroy and Spysweeper. As soon as he finishes backing up his important files I'm going to try to repair XP...I'll let you know what happens.

I tried both ways to repair/reinstall windows XP from the message above and neither would work because search could not find the iexplore.inf (I think that is the correct name for it) file. I tried doing a WIN XP parallel install and it didn't go exactly by the directions but it did install. It then tells you to pick the bottom version of XP when you boot the computer....but that sends me right back to the original version. But here's the kicker....I can get IE to load by going to Windows update (it loads extremely slow I guess because of the system files being deleted) and then I can go anywhere else I want,(loading at normal speed) including updating my antispyware programs. I updated and ran ad-aware (found nothing) and spybot search and destroy which found two spys which it deleted, but when I try to upgrade to the newest Spysweeper it tells me there is a newer version installed and won't install unless I delete it. I tried to delete Spysweeper from Add and Remove and it removed the info from there but not the actual program. I could still open the original spysweeper but can't uninstall it because the uninstaller can not be found. So I went into Explorer and deleted it from there and I still can't install the newer version because it still thinks a newer version is installed. I saved the new Spysweeper 5.0 to CD but it still won't install. I suspect some of the malware must have screwed it up. I'm now doing a search to see if I can find any remnants of it. Any ideas?

Diggler's link looks good. did you try that?

switch him over to FireFox, no more viruses.

His link was the first two methods I mentioned I tried. sfc /scannow would not run at all and the second method couldn't find ie.inf. I seem to be making some progress. I finally got Spysweeper reinstalled after doing the search I mentioned above and it found trojan-downloader-wareout and WINAD and quarantined them. I'm going to run it again, and then run all three antispyware programs and Norton Antivirus in safe mode to see if I can get it clean. Any other suggestions?

Sounds like you're in trouble enough that simply reinstalling Windows may be the best option for you.