Installing a new carb diaphragm kit should make your problems go away. Under $5 for the kit or $20 or so for the whole carb.

I have 52 different IPL's for Briggs 90000 series.
You might be a bit more specific and eliminate 51 of them.

I don't have the model number here with me, I will get it when I get home, here is a link to the manual I downloaded for my model number when I had it previously.

There is also a triangle looking white piece of plastic that is right next to the carburetor above the gas tank that has a spring coming off of it, I took the spring off on accident and the triangle pieced moved around, now I don't know exactly how to put it back together, it seemed fairly self explanatory, but I am second guessing how I put it back together, does anyone have a picture or diagram to show how that should be put back together?

Here is a link that might be useful: Briggs and Stratton, 90000 and 100000 model manual

Typically, when these carbs mess up, it's lack of fuel to the engine. Surging is also indicative of a lean condition.
However, BLACK smoke indicates too much fuel.
To me, that would be an indicator of water in the fuel too.

Think of the scenario where the carb sucks up a "slug" of water. Engine starts to stall and slow down. Throttle plate opens wide. Water finally gets cleared out and the engine gets a big "gulp" of gas, thus the black smoke.
I'd drain the tank.

Either drain the oil and then tip mower completely over to drain the tank,
OR
Let the mower sit overnight with it tilted so that one corner of the tank is tilted down. Next day, siphon from that corner of the tank.

Is the "triangle thing" attached to the throttle shaft?
IF SO, the spring tension should pull the throttle valve open. The governor should move the rod to close the TV as the engine speeds up.
USE caution on the initial start however, in case the engine wants to over speed. BE READY to shut it off, just in case.

aybe this link will have an adequate pic of your linkage?

http://www.lawn-mower-shop.com/carb2.htm

My model number is 10G902, I don't know why I thought it was a 90000 model, but they have the same owner's manual.

I will drain the tank, hopefully that will solve something. My setup is a tank mount diaphram carburetor.

It looks there is a metal bar going through the throttle lever and it looks like I should attach the spring to this lever. I have no control lever, just spring attached to the body of the lawnmower. I guess it would probably help to take a picture, I will do that tonight.

Here is a pic of the setup I have on my lawnmower, please tell me if this is correct or backwards.

I took the carb apart, and the thin piece of diaphram has a bubble and the two pieces of plastic were sort of separated in parts, I guess I should probably replace that. Do you think this could cause the surging issue?

Thanks,
Greg

Here is a link that might be useful: {{gwi:132750}}

It's a VERY good time to replace the diaphragm, since you have the carb off. It's a $3-4 item at the local dealer.
It's one of the most likely "suspects when having carb problems.
While you are at it, make sure the pick up tube screen is clear. Also the "nub" on the bottom corner of the carb is supposed to be the Main Jet. Flush it if you can.

IF the spring is correct, it should poll the throttle valve open when the engine is off.