I thougth that VS was just the programming interface and that you still have to have the compilers separate from VS (or that it has to be like integrated/installed afterwards or something)?

I don't know. My prof used to use VS just to hit 'F5' to compile (or something like that) but otherwise, he used to use Compaq Visual Fortran, which became Intel Visual Fortran.

The very very very miniscule amount of programming that I've done, I've used gcc/g77 and did it using in cygwin.