My first bike! KDX 220

I just got my first motorcycle, a 2001 KDX 220! I plan on using it for trail riding in the open desert OHV areas here in Southern California. I have a couple of questions and or ideas:

1. The bike smokes quite a bit, and bogs in first gear. I know that it has really old gas mix in it? It also blows oil....even go black specs on my helmet. Is this the old fuel mix, or a possible jetting issue? The bike feel strong mid to high...and in higher gears.
2. I took off the pipe to see if I could tell if it had a Wiseco piston....can't tell. Looks original to me.
3. I plan on doing the Top End right away, as I am going to send my fork and shock to be set up for my weight.
4. The bike spooges a bit from the pipe/silencer connection....Is this normal...or part of the possible jetting issue?
5. I also will change the gear oil, and coolant.

I am just looking for a plan of attack to get this bike set up to go riding knowing that I have done at least the basic things to give me a chance of having a reliable bike.

Thank you for your help in advance.

Update!!

Thanks for the replies. Ok, I drained the fuel, and cleaned out the carb bowl. I took a look at the stock settings for the Carb in Cyclpedia, I checked the air mixture screw, and found that it was only 1/2 turn out...when it needed to be 1.5 turns out. This took care of the bogging issues, and oil spooge is much less. I took it for a ride today, and it was great. I still am going to go through and rebuild the top end with a wiesco.

Thanks

I am very happy with the bike so far. I just spent a late night taking the air box out of the frame and cleaned it like crazy. I sealed in between the ring the holds the filter on, and the air box with silicone. I also put on a new UNI filter, I prepped it with a no toil based 3 product Honda air filter kit. I am going to check the compression of the motor tomorrow. Thanks for all of the feedback. One more question...I stopped by Big Lots today, and they had quarts of Kawasaki brand 2T oil...I know it is not synthetic...is it any good?