Load Random Image And a Few More Q`s

Yeah so can anyone give me any pointers on having it so when you click the image it randomly loads a different one from a collection of a couple dozen?
And I want the cursor to change to something like a refresh logo that I design. Also is there anyway to throw a slide transition in when you refresh to the next image rather than just change suddenly?

As well I wanted to ask if anyone knows a good FPS for a Flash Website to have really smooth masks and such. Mines a little choppy at 30.

Thanks a lot