The H4N isn't particularly bad, the 48v phantom power and a/d converters are clean for the price, but just use equipment you're already familiar and comfortable with. I'm hoping you already know the basics of sound editing, such as gain staging properly to get a great recording without clipping your a/d, which DAW you'll be editing and mixing with, and basic tools such as compression and eq.
Biggest tip I can give- Get a good enough recording so that you won't have to fix it in post. Otherwise, know the script backwards and forward, and it wouldn't hurt to get a sound fx cd or pack to reference your own recordings.