Values in drop-down list

Hi, it's my first time posting and I have a problem using Excel that's driving me nuts.

I'm trying to use drop-down lists, and the 2 methods I am aware of for doing this is to use either a validation list or combo boxes under(ActiveX) controls. I would prefer to stick to using the former if possible.

I have no problem working with individual drop-down lists. My problem comes when I try to create a second drop-down list, with the displayed values/options being dependant on the selection from the first drop-down list. For example, say the first drop-down box lists the following as options: Colour, Shape, Size. I want the second drop-down box to list the following sets: [(Blue, Yellow, Red) ; (Triangle, Square, Circle) ; (Big, Small)] depending on what's been selected in the first list. Just to be explicitly clear, if a user selects "Colour" in List 1, then List 2 should present the user with only "Blue", "Yellow" and "Red".

Is this possible using Excel 2002? If not, is it possible using Excel 2007 as I will consider upgrading.

Thanks in advance to everyone who is able (and willing!) to help with this.

Thanks so much, VBA Noob. The instructions were foolproof and exactly what I was looking for. Tried out both methods and they both worked fine.

Thanks again!