You might find this thread helpful:

http://originaltrilogy.com/forum/topic.cfm/Thread-for-all-Usenet-vs-Torrent-vs-Rapidshare-discussion/topic/10677/

I imagine it wouldn't be much of an option for this project on most laptops because HD films drag like hell through most laptop media players.

Mounting a ISO or Disc Image is merely the process of opening it as if you had a DVD in your drive rather than a collection of files.

Most media players have this option somewhere if you explore the drop down menus.

It will open in exactly the same way so if the ISO has a Menu of it's own (like that on a DVD) it will appear on screen first and you will have all the same options you would have if you burned the disc and popped it into a disc drive.