how to ask for confirmation during installing..?

Question

    hi everyone..
 
     I want my c# software to run when pc start for that i made registry entry..

    But if I want to provide feature that when user install software we can ask that he/she want this feature to start program with pc ? if yes then in setup make registry entry else not...I am using Inno Setup  to make set up..
 
    How can i do this..?