Future purchase

This is just a general question about the Jetta. I drive a Jeep Cherokee and will be moving to California soon and want a car for my everyday drive. I have decided on a Jetta. So here is the question, what are some typical problems for Jettas newer than 2002? Also, what engine/trans package would be a good choice for performance without killing the mpg? I drove a 1.8t the other day and really liked but I don't know anything about it.

Thank you!