alexmac said:
I read the two books below which arent bad although the microsoft one is quite basic lacking in detail:

http://www.amazon.co.uk/Introducing-Microsoft-Silverlight-Second-PRO-Developer/dp/073562528X/ref=sr_1_1?ie=UTF8&s=books&qid=1218530493&sr=8-1

http://www.amazon.co.uk/Foundation-Expression-Blend-Applications-Silverlight/dp/1590599764/ref=sr_1_1?ie=UTF8&s=books&qid=1218530516&sr=8-1

Silverlight is obviously fairly new technology so books will take a bit of time to catch up. You are probably better off looking at the silverlight examples and videos on the main Silverlight site.

So to do what you suggest you need to be able to:

Work out how to detect if the mouse is over a picture
Make the picture larger
Detect if someone clicks on it
Change the display of the picture

You should be able to work out how to do this from the various tutorials at:
http://silverlight.net/GetStarted/

Thanks for the reply.  I'll check out the books and the Silverlight website