[It's Just Eric]

Welcome to the forums. Youll find a prolithera of information in the how-to section, and a search will turn up alot of answers to your questions. Somewhere in there theres a write up on pulling the engine codes, so youll be able to diagnose what the check engine light is going off for. As for the wheels / tires, theres multiple threads with information regarding correct size, offset, width, bolt pattern, proformance gains / losses, ect
As for the windows being foggy, it could be as simple as the glass being dirty. Run some fine grain steel wool over it for cleaning the outside. be sure to rinse the windows with a hose really well afterword, and dont use the steel wool on the mirrors. That should take damn near anything off the outside. Give the inside a good windex like normal. If theres still a hazey look to it it may have something to do with the factory tint, though im not sure what exactly
The burning smell could be oil. Get under our car and look around for signs of oil leaks. The smell could also just be moisture burning out of the exhaust (in which case Im just assuming the car sat for a few months before you bought it)

All in all it sounds ike you have got a great deal on a great car. My personal best advice ever, which I give to everyone...Is buy a good tool set and do as much work yourself as possible. This is a great place to do research..youll get all then information youll ever need and thensome. theres nothing mroe satisfying than knowing you wont have to take your car to a mechanic when it breaks (And trust me, it WILL break)
...that and girls think its sexy...
Best of luck with the new car