I don't really want to get into the specifics of entire other operating systems, but as for porting your applications to other computers of the same operating system, what is the requirement? I remember seeing an article somewhere on how to do this, and recently I tried to use an application I made on a friends computer and it failed. I thought I bookmarked the article, but apparently not. Can anyone tell me what I need to do?

Could you provide more information as to what kind of error or failure you are seeing? Nothing horribly complex should be required to run your application on another computer with the same OS. You may want to make sure that all of your application's dependencies are present on the other computer, including dll's (e.g. glut32.dll) and data (e.g. images you may be using).