'91 190E 2.6, new owner with.. issues!?

[Funky_Mad]

So pretty much, I just bought myself a '91 190E manual.. it's pretty nice. My first Benz.
I did have a few questions for you guys though, as you may be able to help.

- When I came back home and put the car on my driveway, I turned the engine off and put it in 3rd gear. Now, on my old VW the car would stay put.. but with the Benz it kept going backward. Is the clutch or transmission tired?

- The gearbox is nice but I found the gears a bit "loose". Is that normal? My mechanic didn't seem to really tick when he shifted and found it pretty normal. It's nice, just different, I guess.

- Now this may sound stupid, but air keep being on when I was driving.. how can I stop it? (the fan) it kept blowing either cold or hot air. I put the degree thing in the white and it stopped, more or less, but air still seemed to be coming out of it..

- Also, I'd like to put some mags I have on but I'm not sure of the size.. Bens size are 5x???
Also, what would be the best size of summer tire to put on it? for both 15'' and up.. (front and rear)
Right now it's running on some studder 185/65/15 both front and back.


Thanks to all!