The intro is interesting, but I would switch out that bass synth for some sort of Cello like instrument, it just sounds flat and droning next to the piano. After that section, the lead instrument could be brought down with the rest of the instruments brought up a bit, to balance the mix. It's also a tad repetitive, but functional.
The ending however, I really really do not like, that cost you half a star. It is too abrupt an end to such a big build up. I can understand it a bit more if that is supposed to be you clicking new game, or something, but it doesn't make it less lame. I would've led that into an entire new section, throw in some midi strings Zelda style and have this big bombastic midi chorus. That, along with the mixing changes, would definitely push that classic Nintendo feel I think.
Good effort man, good effort. :)