Options and If Statements

I was wondering if any of u can help me please.

I want to put 4 option buttons on my form and when they choose one say its called pranks it then displays the combo box and then they select which prank they want to download and then the command button is enabled and it lets them download the selected exe file from my web server?.

Can any of you help me please?.

Please, ask the moderator to move your post into the ASP.Net forum.

This is what i want my program to do?

http://www.youtube.com/watch?v=D16c8YN3rQw