As far as fast food is concerned...I'm a fan of Jack in the Box. The burgers are always great. Sure they're like 10 zillion calories...but that's the byproduct of tasting great.
I also love that you can get to tacos for a buck. You heard that right...a buck...and no they're not authentic...but they're a buck...and not bad at all.
I'm not generally a fast food lover...but I have yet to have something I didn't like from Jack in the box. Just ask my belly...or look at it.