I tried it again, and failed miserably for a good half an hour. Then I decided to try something else. Here's proof that "press up to jump" is the worst control scheme in the world:
I remapped my keyboard so I could use my left hand to jump, and I beat the game in 15 minutes. It was still hard, just not ball-bustingly hard. The worst part of the game by far is the underwater spikes... Jesus, dude. You're mean.
And yeah, it froze at the end for me too. The music was still playing, but the guy wasn't moving and all I could do was close it down.