Boss.
That's some pretty solid composition, I enjoyed it.
By the way, what program are you using? Anvil Studio?
Anything that composes MIDIs should not be in a professional composer's belt. I started off making MIDI's, and finally moved on to FL Studio 8, the aforementioned program. FL stands for Fruity Loops, and is not to be confused with Flash 8. FL Studio 8 is a hefty costing program, though, and most of the people on here most likely have gotten it free via BitTorrent (I don't reccomend the illegal way though). If you continue to use MIDI avoid anything above an eigth note because it gets repetitive.
I don't know any good FREE programs to be honest, your best bet to make decent music for free would be a Tracker, but those produce NES music and are EXTREMELY difficult.