Definitely don't go to the observation deck. It's overpriced and underwhelming. The Burj has the world's largest mall at its feet and a massive fountain which does a musical show every 30 minutes or so.

Every cuisine is available, though pork can be hard to come by unless you're staying in a five star or buy it yourself. The beef is halal, but that hardly matters, a lot of beef in Western countries is also halal even if not advertised, because its easier than maintaining separate facilities for halal and non-halaal. If anything the meat is cleaner if halal.

You want TGI Fridays, Five Guys, Starbucks, they're all readily available. As are tons of amazing high quality fine dining places.

Oh, and you don't need a visa, you'll get a stamp on entry, that's all