I'm going to make a concerted effort to using jigs this year.  My question is what advantages do a jig offer over a similar weight texas rig with same craw?  Also when do you use the different types of jigs (football, arkie etc)?

I am in the same boat as you are. I want to use jigs to but I have never caught a bass while dragging or hopping a jig. I have caught a bass while pitching a jig though. Where I fish, a T-Rigged Craw or Worm rules and I don't know why I ever use anything else to be honest.

As for the T-rig/Jig I usually have both both tied on because the T-Rig is my safety net. If the fish are barley hitting the Jig I will switch to the T-Rig because I tend to land more because they seem to hold on longer. I believe it has something to do with the softness of the bait verses the heavy head they may be feeling.

The two most productive lures ever, T-rigged plastic & Jig-N-Craw!

Why would anyone not have both tied on 24/7/365 is beyound me!

If conditions are dictating a slow presentation I'll start with a jig and most times I'll use a jig, if I'm not getting any action I'll go to  a T-rig. The only time I use the T.Rig right away is clear water, the same with picthing, if I have clear water I'll pitch a beaver style bait but if the water has color I'm going with a jig. The biggest advantage the jig has is the fact it will be easy for the fish to find it in stained water as it will have more water displacement and the larger profile often leads to bigger fish but not always. As for which jigs to use where, well that isn't hard as you can fish them anywhere you want but there are some places where one type is better than another. The football jig for me is a deep water bait where ever there is a hard bottom but I'll often fish a light weight football head in 3' to 5' when I have the same hard bottom area with some scattered chunk rock. Arkiy type heads are the all purpose jig, but I tend to use these in brush, around laydowns and on rocks and I'll use lighter weight arky jigs around sparse grass. Cone or wedge shaped heads I use for grass and I'm not dragging or crawling a jig through grass, I'm lifting it and letting it fall through, now there are other specialty jigs out there that I use too but that is just a basic idea of where to use what kind of jig.

Sometimes the fish just seem like they prefer a worm, sometimes they want a craw presentation. I like that jigs have exposed hooks, I'm gonna try a jig over a t rig craw until I can't can't get away with it. Meaning they either want something else or the exposed hook of the jig is getting hung up too much. And the same for swimming a jig. I try to take advantage of the exposed hook if it is a really snaggy area, ill t rig it, peg it, and swim it. If swimming the t rig needs bulk, ill will add a punch skirt.

You should never leave a peice of structure until you have thrown both!