Uninstalling office 2007 trial creates issues with prior ver

I've been running Office 2000 since it came out. I bought Office 2003 and installed it, but went back to 2000 since MS changed all of the prior menu options and running regression, which I do occasionally changed as well. I really don't have the time to re-learn a program every time a new version is released.

I've had no problems with Excel until I installed a trial version of Office 2007 - what a disaster! When I first opened the programs I had no clue what the heck was going on or how to do the most simple tasks. I found an add-in online that restored the classic menus and tried that out for a while, but in Excel, for the life of me I could not figure out how to create charts.

Again, I don't have time to play around with the software to try to guess how to do tasks that were previously simple, so I ultimately uninstalled the classic menu add-in and Office 2007.

Now when I try to open Excel it asks for the installation disk, which it previously never did. (As I recall, this also happened when I uninstalled Office 2003 to go back to 2000.)

Any suggestions, short of going through the entire, tedious installation process again?

I have learned my lesson and will avoid any future Microsoft program updates/releases.