I'd say you have two ways to go.
Either a really simple, reliable, easy to drive, great handling, W123.
A 240D or 300D. Awesome cars, great first car.

Or you could go with a 300SDL which is more the mercedes tank type solution, but faster and more powerful than maybe you want.

I feel totally comfortable about my wife's safety when she takes the 240D out.


Later,
Tachyon