Windows 7: How can i see what i've changed the default install path to?

Hi & help!
I was having probs installing Office 2007 a while back and whilst using 2 forums for help to resolve the issue, one of the things i had to do was (i think) change the default install path for when i'm installing new programs. The 2 links for the help pages i was using are:
Office 2007 Install Error 2203 - Office Setup
Error 2203. An Internal Error has occurred.

The problem i've created is that now i'm unable to apply most updates for the programs that are currently installed (and thus on shutdown it always tries to apply updates, that fail) and also, i'm not able to install and new programs.
Any help in getting this resolved for me will be soooo appreciated - it's driving me crazy!

Click Start Orb. In search type cmd and hit Enter.
In the command window that popped up type
echo %ProgramFiles% and hit Enter

It should tell you the current setting as in
C:\Program Files

or whatever.

You can take a look at this:
Change Default Installation Directory In Windows 7 & Vista

But before messing with your Registry make a Restore Point and/or use ERUNT
to back it up.

I just did search and took a look at the registry settings in the link. I don't know if it works. Back things up before messing around with it.

Thanks MilesAhead - I'll try this later on tonight once i'm back home and let you know how i get on!