Okay I'll chime in.
Welcome aboard. First is the oven going to have a metal layer outside and inside with the insulation between.If so you can use home fiberglass rolled insulation just be sure to remove the paper backer or vapor barrior as some call it. Go with 4 inch min.Second why the window on 2 sides? Third if it's not sealed then you may skip the vent(some peolpe will cry about this but it will work fine).As long as it has a leak somewhere for expanding air to escape so it won't build pressure.If you find the fumes bother you (and it does bother some people) then install the vent.Four oven lights from a regular oven will work.Most hardware stores carry the bulbs for them.