You're pretty much going to have to mess around with it until you can get
everything loose.

Presuming the regulator is stripped and not the handle, you may be able to
manually lower the glass by pushing it down. If not, you may be able to
get your arm inside and unbolt the window from the regulator while it's up
in the door. Be prepared for nasty scrapes if you're doing this. Or, you
could try to unbolt the regulator from the door and move everything to a
position more friendly for removing the window from the regulator.