Space questions for story.?

I'm working on a story and need some space questions answered. Like if a spaceship was left out in space unmaned (had a crew but they are no longer there) for a year or so what would happen to it? what physical changes would occur? If people boarded that ship what would it be like inside? Would there be oxygen? I've seen the movie 2010, which a similar thing happens but i wasn't sure if that was realistic.