What width tires for trails?

I7 Extreme
I7 Extreme Posts: 228
edited September 2013 in MTB buying advice
I'm not sure what width Tires would be best for trails, I Want some which would be quick and grippy (as everyone does). I'd mainly do red trails but I would do blue and black aswell. I'm thinking of getting a tire in the range of 2.1 and 2.35 on the front and I don't think the rear matters (1.95), or does it? which width would be most suitable?