Hi,

I'm french and living in Leeds since end 2007.
If your company cannot help you for the flat, you can look on internet add for sharing house where room are always furnished. I live in Roundhay which is a safe and nice district (around 20 min in car from White Rose).
If you prefer student life you can see on Headingley district

Concerning the car, I would advise it !
There are bus but no exceptional...
Hope it can help,

Alex