We've talked in the past about aids some one could use as a GM to help enhance the gaming experience. Let's start with music.
Music can really set the tone for a battle or an intimate meeting. Why do you think video games spend so much money on having actual orchestras to play their music? So here are some of my suggestions:
1) For battles, if they are big and epic, or even small ones. I recommend music from Lord of the Rings, many video games, or other fantasy genre movies. A lot of classical music is awesome for this as well, (In the Halls of the Mountain King, comes to mind). You can put them on loop for a long battle or pick a huge selection to make sure you have enough. (We've had a single battle last 5 hours, so be prepared.)
2) For a certain area the party comes upon. Wouldn't some creepy music for an old tomb be mood setting? Or light, airy music when they come upon a grand old forest housing the ruins of a fabled city?
3) Theme music. I've mentioned this before, but having a "theme song" for each character is actually a fun idea. Play it softly in the back ground while they are doing something awesome or character developing!
I know this puts more pressure on the GM, but your players will love the effort!
Next: Physical Aids