Application that would set default application for file types

Question

Do you know of any application that could define the application for opening different file types? For example, setting a default application that would open .reg files. Or if there is not any then what do I do to set it?

Answer 1

WinXP and below;

Tools, Folder Options, File Associations

Win Vista and above;

Start, Control Pannel, Default Programs,
"Associate a file type or protocol with a program"