This is the easiest, non-technical, method:

<sub>(I'm on Snow Leopard, I've edited these to match Mavericks - the exact buttons to click may be wrong)</sub>

1. Open Calendar.app
2. Make a new event *today* for *00:00*
3. Set it to *repeat every day*
4. *Alert* should be *Open file*. Select *Other* > Find iTunes in *Applications*
5. Make an Applescript and type this: `tell application "iTunes" to quit`. Save it somewhere
6. Make another event *tomorrow* for *05:00*
7. Set it to *repeat every day*
8. *Alert* should be *Open file*. Select *Other* > the applescript you made above

Done!