Fast food is one of my downfalls. If it's unhealthy then I love it!

Pizza: Domino's is nice but very expensive. It's rare that I see it but as @suzukir122 mentions, Sbarro is real good pizza.
Tex-Mex: I do like Taco Bell but the portions are small so I always have to order two of what I want which ends up not so cheap. Still need to try out Chipotle.
Sandwiches: Subway is good and I do go there occasionally.
Chicken (my favourite): Nando's is always great, hot or extra hot. Otherwise it is KFC, PopEyes or occasionally Allen's if up in Manchester UK. Waiting to try Chick-Fil-A.
Burger (second fav): Five Guys (excellent but damn expensive), Burger King, Wendy's. Fatburger (Had a few amazing meals there in Los Angeles many years ago at Wilshire Blvd and Crenshaw Blvd).
Breakfast: Greggs and Tim Hortons.

You could add Taco Bueno (they were featured in King of the Hill) to your list, though it may not get any votes.  My last trip there it may have been taco, but it was not bueno.

There's also Taco Time and Filibertos, and for burgers there's Blake's Lottaburger.  That last one is going to have to go on my favorite burger list.