T.F.
ETA: Lori... you nailed it. How did I leave those wonderful places out!!! Great ideas.
I live in the Dallas area (North Dallas, Allen, Plano Frisco areas) and there is a ton of things to do. If possible, visit Fort Worth as well. The stockyards in Ft Worth are great.
A lot of it depends on your interests.
The JFK Museum and Book Depository is a must see for many who visit the area.
George Bush library is awesome located at the SMU campus.
Sports? Texas Ranger game, indoor skydiving, Top Golf, visit/tour Cowboy stadium in Arlington and the new Cowboy workout facilities area at The Star in Frisco.
Concerts: AA Center downtown and Cowboys Stadium in Arlington.
Food: OMG where to start. Depends on your budget but we have some fantastic restaurants.
It sounds like your children might be a little old for Hurricane Harbor and Six Flags but it is there.
Shopping is awesome from the outlet centers to high end.
I am not that familiar with 35 but I think you go through the area with Winstar Casino which has a lot of concerts.
What area of town are you looking to stay? Great hotels downtown the W. Gaylord out by the airport, lots of very nice Marriott resort type hotels.
Many of our roads are tolls and they bill you based on your tag #. I think my card gets billed about $40 a month for tolls. You don't stop and pay, cameras take all the info and send you a bill. You might check out ntta.com to check out any rules or info for out of state or cars with no toll tag.
If I think of anything else I'll post it. Feel free to PM with specific questions and areas as well.