Animation To Play When Mouse Over The Area But Still Other Times?

I'm creating a mini site for a course I'm doing and I have a row of buttons that have an image of a character that I want to animate when the viewers mouse goes over them. I'm not good with action script and I'm stumped on what to look up when googling for an answer.

Ideally I would like the row of buttons (that the chacters sit in - and when they are clicked they go to that characters main page) to animate - ie blink or move slightly but when the viewer hovers their mouse over them they then go into a new animated sequence - so I guess that would require two movieclips - so that would mean that the first animation of a blink would run all the time (I can do that bit! ) but how to get it to switch to another movieclip for the duration of the mouse hover - and to only play when the mouse is in that area (I've done scrolling image bars before and I hated the way it scrolled even when the mouse was no where near the images!)

this is a very rough bare bones of the flash page I'm doing - I've attached it to my main website just so others can see what I'm talking about. [URL] all the squares at the bottom will have a characters in them and I want them to do very subtle things like blink or the occasional wave but when someone goes to click on them they wave or jump around - this would stop if the viewer then moves the mouse away and it goes back to the initial movieclip.