You might be a little young to care, but you might consider visiting the Texas School Book Depository
where they offed JFK. If you like cajun food, look up the closest "Pappadeaux"s. http://www.pappadeaux.com/pdxlocations.htm
The Dallas Mavericks have a pretty good NBA team.
Just some thoughts.
Last time I was there 10 years ago or so.....I visited Beni-hanas for dinners, went to a gun range to shoot a handgun...but if you're looking to fish....google search and find some bass guys that will take you out....if you're in for some commuting....hit the gulf, time permitting....best of all..have a good time! I had to drive by Texas Stadium on the way to training every morning....sure is a dump up close..well not the stadium, the stuff around it......enjoy, I hated Dallas personally....Austin was soooo much better a few years later!!!!
DB - Gilley's is in a suburb of Houston, TX... not Dallas.
Madcap - Dallas is in northeastern Texas... about a 10 hour drive from the nearest salt water.
Tr - Pappadeaux does have decent cajun food for a chain restaurant... but IMO, if you want REAL cajun... you probably ain't gonna find it in Dallas.
Jacob - As mentioned... Dealy Plaza (where JFK was killed) is an interesting place... but overall... Dallas is just a big suburban-sprawl city with nothing of any real specific interest going for it. You can get a good steak dinner there... but you'll find that it's pretty much just like any other large midwestern city. They DO have a lot of "Gentleman's clubs" in Texas if you're into that... and you can drink alcohol in them too. Tup: