Add/Remove Programmes Problem

I have Windows 2000 on my PC and have recently found that when I go into Add/Remove programmes to remove a programme, a lot of the programmes are greyed out and will not perform any function when I click on them. I have some software which I therefore cannot now remove. The only programmes that do work are those installed recently. The majority are greyed out. Can anybody advise in simple layman's lingo.

Thanks

Are you logged onto the machine as an administrator?

Yes