WinRar is like WinZip They take you folders files the you want and compress them in to one file.

(e.g 1) you take a music MP3 file and it is 5MB you compress it using WinRar or WinZip and it is now 2MB

(e.g 2) You have a lot of files you want in Just one file you can thern use winRar or WinXZip to do this.

Just like when you make a new folder and you put all the files you want in that folder. But with WinZip and WinRar you can compress it. If you were going to e-mail somone some software you would have to send them 20+ files say 30MB But if you use WInRar/WinZip you could send them one 15MB. when they get all they would have to do is uncompress it. This is why on LimeWire you see loads of Rar/Zip files, There easy to work with and take less longer to download.

Now for you ISO

Iso file are said to be very good as they are compatible with allot of software. I haven't really used them. I have made a DVD movie ISO/UDF File with CloneDVD that was 4.3GB it only took 20Min

If it is a game it will most probably have a protection on it safdisk, Tags somthing like that. You will need a software called CloneCD Or BlindWrie. I have both, but I recomeand BlindWrite current version of Blindwrite is 5.1.6b go here and read up on it.

http://www.vso-software.fr/