about clicking on subject and continuing

Hey guys I need help with action script 2.0 for flash. I'm totally new in this subject.
There's this assignment where I need to include at least 1 action script in my animation and I've figured out what to do but I have no idea what keyword to search for this. So I hope someone can help me out.

What I'm gonna do is that in my animation , there will be 3 items , let's say A,B,C and a person standing beside it. And then the user will click on either one of the items and the person will start talking about it,same goes to item B and C. Then there will be a continue button on corner right so I can proceed with the animation, also is it possible to make the item unclickable once being clicked?? so that the user will not be clicking on same item more than once.

It'll be good if there's a you tube link or some video ,thanks :)



PS: Yes ,only action script 2.0,cause my lecturer is using an outdated software ,so she asked to use only 2.0 lol