Remote Desktop Connection on Windows 7?

Hey, I have a few questions about RDC, I've never used it before, but i was wondering how it works.

I have it set up now at home, I can access all 3 of my PC's and it works fine.

My question is, how can I access them from school, or from work using RDC?

I know about LogMeIn.com, but I would like to share files between computers, and the free version doesn't offer it.

I would also like to access my computers while on vacations, but I don't know how to access it from somewhere else. Is there a way to set it up so I can do this? What would I need to do to be able to access it from across the world? Like I said I use LogMeIn.com now, but I really want to be able to exchange files and whatnot, so is there a way to do this?

I'm not completely computer illiterate so I could probably do it, it's just that I don't know what to do.

thanks in advanced.