My current highscore on the uncheatery way is 288.
I created nine characters in total before giving up, all of them were killed by either zombies, carnivourus plants or hedgehogs except the first one, he was killed by a dark frog that jumped out of a fountain.
this was an interesting experience.. banana peels make fairly bad weapons... but even worse, they keep rotting, I havent lived long enough to tell but I'm worried that they'll spoil completely at any moment.
EDIT: It was too tempting to resist, I created two more characters but with the "peels as traps" approach, the first character successfully killed a hedgehog by luring it to step on banana peels and slipping to death, he then died in the same way when trying to pick up the peels.
The second character lived much longer and I skipped the idea of using the peels as traps, he lived mostly thanks to two mustard gas grenades and a wand of striking, he made it to UT2 and had to go back to town to buy new bananas twice, because of them spoiling, he was eventually killed by a kobold which stabbed him in the head.