Problem with AC/Heating (Blower Motor?)

I know jack about cars, first of all.
My problem is: when I turn on the AC or the heating nothing happens until it is on the highest setting, then I get an awful whirring noise coming from the glove box. Nothing comes out of any of the vents.
Today I vacuumed out the vent thing located behind the glove box (where the noise was coming from) as it was full of crap (leaves, small twigs, etc. I don't even know how) thinking it would solve my problem, and it didn't.
Forgive me for the description you're about to get because I have no idea how to describe this properly but I'm also having issues with the lever that allows you to change between (I think this is what it does) circulating air and using the vents? It gets stuck and I have to tug on it pretty hard.
Any help would be greatly appreciated.
On a side note, my light doesn't come on when I open my doors. Yes, I have it on the right setting, it is not off.

High speed only means blower motor resistor is bad-- twigs in blower vents is bad- is probably what is binding your fresh air/recirc air door...need to remove blower motor and clean out all debris....

Interior lights not coming on is a bad door jamb switch-- wiggle it, clean it, clean corrosion of it, still not working? replace it....do lights work of other door? to be sure you have correct switch..

Thank you so much for the response. As for the air door, I've removed all the debris and it's a bit sticky still, and I mean literally sticky. I reached behind the glove box to wiggle the switch a bit and it worked, but my hands were a bit sticky.