Trying to download a program - Help !!

I am confused, I want to download a fairly large program, several hundred MB, off of Limewire. When I type in the name of the progarm, learn to read then maybe you will not break the simple rules of this forum, I get back choices which are .zip files from 110kb to 770Kb in size, there are also .exe files of similar size. My question is how can I get the real program because I am assuming there is no way even a .zip file of that size could be a program which is a couple of hundred MB. Is there something I am missing? How big should a .zip be to equate to say 200MB. Also, should I always be looking for one with a "crack" . What does it mean when I see these downloads that say with crack?
Also, what is an .iso file

Thanks for all the help.

Please DON'T Double and Triple Post. It's against Forum Rules.

And on all of your questions... Use Google. You have a lot of research and reading to do.

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