Repair Windows Script Host (WSH/scripting) in XP SP3? (Need a true guru!)

I believe I may have a corrupted Windows Script Host installation, but I am not 100% sure.  I'll try to provide as many details as possible.  I try to keep my computer running smoothly and can usually fix most problems but this one is driving me nuts!

About a week ago I installed TurboTax 2009 to do my taxes and noticed that every help link I tried in the program brought up an empty help window.  I thought that was odd and in the end I ended up installing it on one of my other computers and it was fine.  Yesterday I was looking around the internet and came on the idea that maybe the problem was related to Windows Scripting.  I saw some people mentioning script errors in 'Windows Help and Support' so I opened it up and looked around.  Sure enough, I encountered two script errors.  For example, if I click on 'Fixing a problem' I get the following error:

Internet Explorer Script Error
An error has occured in the script in this page.
Line: 71
Char: 2
Error:  Automation server can't create object
Code: 0
URL: ms-its:C:\WINDOWS\Help\ntshared.chm::/shared.js

Whether I click Yes or No to continue running scripts, I then get the following:

Internet Explorer Script Error
An error has occured in the script in this page.
Line: 492
Char: 10
Error:  'xmldoc' is undefined
Code: 0
URL: ms-its:C:\WINDOWS\Help\ntshared.chm::/shared.js

The Help window then shows information on "Fixing a problem", but here and there in the text is "XOX".  It appears that wherever it says "XOX", it should be saying "Windows XP" or something along those lines.  I then tried to open up some of the many CHM files inside the Windows\Help folder.  Not all of them cause errors, but several do.  For example, Magnify.chm causes the first error mentioned above followed by another script error that says "Class not registered".  It also displays "XOX" in places as well.

It seems pretty likely to me that the lack of information in the TurboTax help windows is related to this other problem I am having.  I'm not sure when this all started but I suspect it was several months ago.  A while back I noticed that Pogo games won't run on this computer because it says we don't have the correct version of Java installed.  I am now thinking that perhaps Pogo.com uses javascript to determine the Java version installed and maybe that is related to these other issues as well.

Please believe me when I say I have tried almost everything I can think of.  As mentioned above, I can usually fix things like this but I am up against a wall.  I have spent hours looking online for help with this and have gotten nowhere.  Many sites say it is a security problem in IE.  I have tried setting the IE security to completely relaxed and it didn't help.  I even tried rolling back to IE6 and it didn't help (I am using IE8).  I also tried disabling all IE add-ons and it didn't help.  I have tried replacing as many WSH-related DLLs that I am aware of by taking them off another XP SP3 computer that is identical as far as the OS and Windows Updates go.  Didn't help.  I was going to do a Windows Repair but for some reason my USB keyboard didn't work with it.  I suspect it is because it is connected to a USB hub, but I didn't try connecting it directly to the computer.  I kind of took it as a sign that maybe I should try to fix it again before doing something so drastic.  Unfortunately System Restore is out of the question because just a few days ago I deleted all but the latest System Restore file.  Why, I don't know.  I've never needed to use it before and figured it was a waste of space.  Don't worry about the 147 GB of free space on my C drive.  I could just about kick myself for deleting those now.

So anyway, I really suspect that something is corrupted.  Whether it be files or keys in the registry I don't know.  If I knew which registry keys are related to WSH and all of the files that are related, perhaps I could get this straightened out by comparing to another XP computer I have.  It could be a corrupt IE installation, but I tried rolling back to IE6 and back again to IE8 so it seems unlikely.  Also, other than the minor Pogo problem mentioned above, I don't have problems on websites.  It seems to be related to the local scripting host (as opposed to server-side scripts on websites).  Incidentally Pogo works on all of my other computers (running identicle service packs & updates) and it does work on this computer but only in Mozilla Firefox (which from what I understand uses its own scripting host rather than WSH).

I have looked on Microsoft's site and have seen downloads for Windows Script 5.7 (I think it was 5.7) but when I try to install it says that my service pack is higher than what it wants to install so it aborts.  I have found articles on the Microsoft website that mention fixing or repairing WSH but they are for older OSs.  I cannot find any way to repair my WSH installation on XP SP3 nor any advice on doing so manually.  I guess I can still break down and do a repair install on the OS but I've never needed to do that before in almost 20 years of Windows computing.  I know I will just need to reinstall patches but I'd still like to avoid it.  I even thought about biting the bullet and installing Windows 7 until I found out I can't do an in-place upgrade and will need to re-install all of my games, and dozens of other programs.  I'd really like to fix this problem if possible, but I supposed it isn't the end of the world if I can't.

Any thoughts or knowledge you guys can give me on this?  I'd appreciate it!