I have Office 03 and Vista and they are working fine except for this issue...My PC came from Gateway with a trial of Office 2007 and I removed it (so I thought) before I installed 03 so I could avoid and tangled up files. It's still hiding something somewhere because I keep failing MS Office Validation due to the 2007 version being considered "not-genuine". My 2003 copy passes every time I try. I can't seem to locate a fix for this short of a complete recovery which would really suck since I just got things really working well.
Make sure you do not and up in the same situation and I would even ask the store to remove the trial for you of they will so that you can pin it on them if you have an issue.
Good luck, otherwise I am liking many other things and once this is resolved will consider this an improvement.
'Getting ready to buy a new computer, hopefully today, and want to confirm that I can use my "old" MS Office 2003 program with Vista. Anyone know for sure?