Infamous 'updating environment strings'; isn't this fixed yet??

Question

Ok this is killing me. I know there are posts, and I have weeded through them for the last hour.
None of the solutions on here are working. Every install attempt of quicktime hangs up at the 'updating environment strings'.
I've used CC Registry Cleaner mentioned in one post. I've used Windows Install Clean up. I've uninstalled QT, deleted all folders including ones in System32, restarted, NADA. I've even read it's a firefox issue. Unistalled that, tried the QT install, NADA. Ugh. somebody bottle me please.
Another annoying thing is that I could not uninstall itunes without just deleting the folders, like it was 1992 all over again. It wasn't on the Add/Remove programs in CP, bizarre. Its still in my Start Up too...
So question 2, how should I go about uninstalling Itunes? Downloading the setup file and selecting Uninstall? Will that work?
More importantly I NEED the new Quicktime. It baffles me that this is MADE to be installed with itunes, itunes should be a stand alone. I'm about to buy an Ipod, but not if I can't install this!
Windows XP by the way.
The file, QTPluginInstaller.exe is doing it I believe, right when the icon is being created. This file is taking up 99-100 percent of my CPU when it hangs up. Coincidence maybe?
HEEEEEEEEEEEEEEEEELP. I need a new MP3 player and this is literally making my clynical. Appreciate any help...GREATLY!

Answer 1

I did the following on a windows XP Pro machine and got it to install finally:
so after months of reading forums and pulling my hair out..here's what I did to get to work: ( windows XP pro )
after a fresh reboot:
1. Open a windows explorer window.
2. right click on C:\ ( or your main windows drive )
3. ->properties->security
4. this will display all users and their permissions to this folder. click on add, enter your user name, and give yourself full access....this will take a while, it recursively sets the permissions of every file and folder on this drive for you to have full access ( I know, it sounds dangerous, and it probably is..but I got really f'ing frustrated..and had to go to extreme measures ).
5. right click on the QuickTimeInstaller.exe file->run as: click off of the check box that says "Protect My Computer From Unauthorized .....etc..." - click on OK..
6. I chose a folder other than the default ( I think ...\QuickTime3 )
and I just about soiled myself when it actually worked...I hope it does for you !!!
thanks
Gen Zod