a few questions about making doors for a cage

[Chandra2]

I will be buying the plywood on monday and I think I have the cage pretty well planned out.It will be 8x4x3.
My question is how to make doors.Ive made doors for an outdoor aviary and they are not very straight.I had to doctor them up with those metal corner things.So Im not to sure if I can do better with glass doors.

Anyway I have two 1/4 inch tempered plates of glass I want to use for the doors.I dont have a router, is there a way to make door frames without a router ???

Im not sure that sliding glass doors will work for a monitor.Im pretty sure they can knock them off the track or open them if they are determined enough.

I found a router at harbor freight for cheap I wonder if that would do?
ANY ideas for doors would be great..