KRK monitors are very good for being able to hear what's happening in a mix. I own a pear of Rokit 5s.
Any old interface is great nowadays. The Presonus units are very nice, reliable; same with MBox. I use a Presonus FireStudio 26x26 and a FireBox....but Firewire is going out of style, giving way to USB. Presonus' new AudioBox USB interfaces are great.
For the type of stuff I think you're after, Ableton Live is pretty much it these days. For regular audio production I use Cubase. All the pro studios are either ProTools or sometimes Nuendo, but PT is where it's at for audio and lock to picture.