Need Help in many places, over thinking.

[The Arquido]

So, I've started reading this board and it is quite helpful but it's easy to get in over your head if you are a beginner like me.
I've included my map that I am working on and I'm over thinking everything.

First of all, scale. I'd like for the continent to be about a 2.5 to 3 month horse ride from tip to tip if conditions were optimal which of course they aren't. I've done quick math and realized that my continent will be about 3k miles from tip to tip. Not sure if I am comfortable with that. Thoughts.

Second, I have no idea where to place my mountains. I originally started down the middle left then split the two lakes and finally cut back in where it says "wetlands" and stopped. This is the worst part, because then I start worrying about weather patterns caused by the mountains and sea.

Third, the "WHAT" area. What does it need? Part of the hot area will also be jungle. What separates a jungle from a desert?

Fourth, I'm going to place a city between the D and the S of "Wetlands", what kind of climate is expected on the inner shore of a peninsula?

I have a million other little questions, I just need a kick in the butt or a couple suggestions to get in gear.

The only thing on my map proper is the continent and sea, all words and outlines are just to show what I've got in my mind at the moment.

Any comments are appreciated, I know this is early on in the process and very general in scope. Thanks for your time.