Martyn, you don't even need simple VBA for that - try using Action Settings.
Right-click any element and click the Action Settings option. This will
bring forth the Action Settings dialog box with two tabs for Mouseover and
Mouseclick events.

Does this solve your problem - or was there more to your question? Do get
back and let us know.

Geetesh is right.  What you described can be done without VBA at all, but
if there are a few more things you want to do, you might need VBA.  
Fortunately, you don't have to learn it "in full."  You can learn just
enough to do a few simple things.  You might want to check out some of
the examples on my web site:

http://www.loyola.edu/education/PowerfulPowerPoint/

You can use them as they are (just change the PowerPoint slides to suit
your purposes) or learn to make small modifications (my book describes
how to do that).  I fully believe that people can do some basic things
with VBA with very little VBA knowledge.  Obviously, the more you know,
the more you can do, but because you are building on PowerPoint, which
you already know, you can do a lot with very little VBA.

--David