Help with baitcasting rod/reel

Hi all, first of all I would like to say I really enjoy the newsgroup. Your
tips, stories, etc. make the days at work go by a little faster and the
fishing a little easier each time so thanks for that. Anyways, to the
question...

My buddy recently gave me a baitcasting rod and reel and I've been having
quite a hard time learning to use it. It currently has 12 lb Trilene XL
Smooth Casting line in there. The way I set the spool is lets say I have a
tube on, I will set it so that when I press the release button, it will
slowly take line, not drop freely to the floor. I also keep a steady
pressure on the spool when casting but almost every time, the line gets
loose on the spool and eventually tangled. I was wondering if I'm simply
using the wrong line for this type of reel or if I just need more practice.
Honestly I prefer using braided line (fireline) because of lower memory and
better sensitivity but my buddy wasn't sure if I should use it in a
baitcasting reel. We fish mainly for Smallmouth and for the occasional Pike
around here so I don't really need a heavy line. I currently use a light rod
with spinning reel spooled with 8 lb fireline and I find it does an awesome
job. Anyways, any help on which line would be best and any tips on casting
and best setup for the reel would be appreciated as I really would like to
learn to fish with this type of rod/reel combo.

I know I'm asking a lot here but go easy on me guys I'm new to fishing and
still learning day by day!

Thanks!

Dre