It's a good idea to just do a tape measure bf% to get an idea of where you are. here is the online calculator that I use. There are many, but this one seems to fall right in the middle of the road. Dosen't really matter, but having a starting point and using the same measure will show trend.

Sorry to ask, but are you male or female?

Calories matter in so much as you need to get enough. Try plugging in a few days at www.fitday.com and see what you get.

What is your goal?

Let's just say that you are at 25% body fat. Let's say you want to get to 20% bf. that's only a 5% difference, and your body is not going to really want to lose that last 5%. Losing 2% in four weeks is good, I lost 5% in 12 weeks, doing bfl.
Do you want to SUSTAIN your loss? I know it sounds like a no brainer question, but your inquiry regarding efa's and creatine makes me want to ask.
A few thoughts on guidelines:
IMHO, you need 10-12 times your body weight in calories. This is a highly debated fact, but one that seems to work well with MOST. You should try to get 1gram of protein for each pound or KG of body weight, whichever you feel most comfortable with. 35 grams of carb or less, but eat them before, during or directly after your workouts combined with a very lean protein.
Try to intervel train on your bike go as fast as you can for one min. then less and less for the following 3 min. until after 5 min you go as fast as you can again.
Be careful of overtraining your upperbody if you are doing the whole thing in one day, and then again in the same week.

It's been proven that having more muscle increases your metobolic rate. Working with weights more will increase muscle mass.
I am currently doing the t-dawg with NO cardio and lost 1.6% fat in 4 weeks, weights only, 4 days a week, and one free eating day a week.
Hope this helps,
Brenda