I see from here that it's possible to change the function of hardware keys for MicroB.

Is it possible to change the behaviour of the escape key so that a long press of the escape key doesn't close the browser?
I've lost count of the amount of times I've inadvertently closed the browser while meaning to scroll whilst using the n800 in bed in the dark .

A long press of the escape key force kills the foreground application, so it's not so much a question of changing microb's behaviour; but changing that of Matchbox.

I've had a quick poke around and not found any configuration file for Matchbox containing anything obvious, I'm afraid. It's possible it's something the Mer guys might've come across, though.