You've gotten some good answers. I'd like to add that sometimes the things we lik least (fitness wise) are the ones that need the most work or would benefit us most. I personally LOVE weight training, and have a tendency to concentrate more on that. I recently discovered that my cardio capacity has decreased when I tried to do a cardio workout that I'd done previously, so now I'm going to focus a bit more on cardio.
Generally, guidelines for weights vs. cardio say a minimum of two full-body weight workouts and 3 cardio workouts per week, but you can do them on the same days.