So I've had this problem with my Desire for months now, and I still can't find anything about it when searchin on google. Only found this post which sounds like the exact same thing that's happening to me.

Basically it only crashes and reboots when I'm at my university dorm room, though it used to work fine there for over a year. It can crash multiple times in a few minutes or only once an hour. I just came back from a 3 week trip 250km from here, and it didn't crash even once.

Home button started to respond less and less too, but that seems to be 'normal' these days when your phone gets to the 2 year mark.

My Desire will be 2 years old in november, it's running android 2.2.2