You have 3 (now maybe 4) versions of MS Office installed within the
same instance of Windows?  You don't run into problems with the same
registry settings being used by multiple versions of the same program?
Are you using SVS from Altiris (acquired by Symantec) to load only one
copy of whichever version of MS Office you want "installed" at any
time, or running them in VMs?

http://support.microsoft.com/kb/q218861/
Read the paragraph starting with "You cannot run multiple versions of
Outlook on the same computer."
http://support.microsoft.com/kb/828956
And the paragraphs starting with "Microsoft Office Outlook 2003 cannot
coexist with any earlier version of Microsoft Outlook."

You need to install earliest version of Office first, 97 & 2K via custom
install to a version specific folder.
2002 & later allready install to version specific folders by default
Update each version prior to installation of the next.
Amend shortcuts after each install, eg Word>Word2k
Only a single instance of outlook can be installed, unless installing to a
virtual machine

As to whether they will all work without problems.......??