The VW Jetta has long been a main stay in the German car lineup and a reliable car for many drivers. Having owned one myself and with a few Jettas in the family, I can confidently recommend a good tire for this vehicle. For the 5th generation model, current sizes 195/65-15 or the 205/55-16, there are several good options.
For those drivers looking for a nice riding, all-season touring tire, I would suggest the Michelin Primacy MXV4 (pictured at left). This tire is very smooth and quiet and offers fantastic all-season traction.
Drivers looking for more of a performance tire will like the Yokohoma AVID ENVigor. This tire is also very smooth but has excellent handling characteristics and is a very good value.
If you're thinking about a winter tire for the Jetta, I would consider the Michelin X-Ice XI2. This tire has top-notch winter traction and is very stable on dry pavement.