If you go to Granbury, consider staying overnight and booking a room at the Nutt House, on the courthouse Square. It's a charming early 20th century hotel that is being carefully restored to its former glory. It's just a neat place to stay, a far cry from the cookie-cutter motels right off from the freeway.
Just a short 20 minute drive to the southwest of Ft. Worth is the county seat town of Granbury. In Granbury you'll find a neat array of smalltown shops and restaurants grouped around a classic couty courthouse. Also, the Granbury Opera House is here, featuring excellent productions of plays and musicals by energetic and talent casts. Hi Katie!
Irving is a city right next to Dallas. Actually, I lived in Irving for a bit. There you will find Texas Stadium (where the Cowboys play,) Las Colinas, Mandalay Canal with Venetian-style water taxis and waterfront, Movie Studios at Las Colinas, the Mustangs of Las Colinas (statues at Williams Square,) and more. My favorite hang-out in Irving was Judge Roy Bean's restaurant...I never ate there, but whenever you bought a beer during happy hour you would get a spin on a wheel to win prizes...such as another beer, a shot, food, or nothing.
Downtown Mckinney - it's a historic district with an old court house, many antique malls, cafes, and even a British Baker(107 South Chestnut)...in case you want really good food and need a scones fix. The neighborhood around downtown is very nice too. Many old houses/mansions with spires and other fancy architecture.
In 1997, I visited Nevada Texas outside of Dallas because I had a friend who lived there. There is very little in Nevada for the tourist.