Basially the way food works simply:
Protein - Repairs muscle cells damaged during training.
Carbohydrate - Stored as glycogen on the walls of the liver and in the muscle cells as a ready source of energy.
If you eat too much of either of these and there isn't sufficient space to store them the body converts them to make them easier to store.
If you have too much protein some is converted in carbohydrates and if you have too much carbohydrate it get stored as subcutaneous fat. For survival this is brilliant but obviously not for remaining lean.
So say if you did take too much protein, the likelyhood is that it'll be stored as carbohydrates and you won't see a massive net fat gain.
Our conditioning coach said no matter what you eat make sure you eat protein, because you'll repair your muscle cells resulting in a gain in muscle size as an adaptation to training. But you gotta take carbohydrates on too to make sure that as much of the protein is taken up and not stored as glycogen.
In terms of a ratio of carb

rotein intake I'm currently rewritting an article to make it simple for new trainers and I'll be posting that on the website when G sets it up.
CREATINE
In terms of the creatine I'd recommend taking it but here's some tips on how to get the most out of it:
- Take it with grape juice
You only need to take it with a small serving of grape juice (half pint at the most). The reason for taking it with this is because it's high glycemic and means the creatine will get taken up maximally and quickly
- Drink a lot more water
Creatine causes the cells to take on more water which will result in a bit more of a pumped look. But you have to pretty much double your water intake too (6-8 litres a day ideally). Make sure you don't just drink water though because it will flush out your system completely. Have an isotonic drink through the day too the make sure this doesn't happen.
- Cycle it
Like it says on the tub for the first few days I'd take it four times a day at regular intervals. After that you can take it just after training and before if you wish.
Creatine works as an aid to recovery when training anaerobically so yeah it does mean you'll recover from sets quicker and be able to get a few more reps out hopefully resulting in a net strength gain.
Hope that helps.