mom4, I'll second HarryO's reply. It'll be an AWESOME trip. I spent five years as a long haul trucker and some of my favorite trips were on I-8/I-10/I-40 in the Southwest! The Southwest really has some awesome vistas (along with miles of fairly boring scenery) But you'll enjoy the trip. At the first truck stop you pass, pick up an "Exit Guide"; a book that tells you what restaurants, motels and other businesses are at/near that exit. The guide also lists the mile markers of rest areas and will tell you if the exit is on the left or right and if you can't reenter the Interstate at that exit...
Unless you want to see New Orleans, it's shorter to take I-12 across the top of Lake Ponchartrain and over to Baton Rouge than staying on I-10 thru N'awlins!
Traffic thru Houston is pretty much "rush hour" 24/7 so relax and enjoy! Suggestion: Consider taking U.S. 90 from San Antonio to El Paso. Yes, it's got plenty of stretches without towns, but not so few that you can't have a comfortable fuel reserve if you keep an eye on the gage. The home of Judge Roy Bean at Langtry might be of interest to you. If you have the time, you can walk across the border into Mexico (
DO NOT DRIVE!) at Del Rio and the scenery near Alpine is breathtaking.
If airplanes are anybody's thing; Tucson, AZ is the home of the USAF's aircraft "Boneyard" (at Davis-Monthan AFB) I'm not sure of it's proper name these days, but the aircarft disposal, storage and disposition center does everything that the Air force needs done with excess aircraft. I think they still have tours, but you pass the Southern side of it on I-10 East of tucson.
Mom4, one of my favorite things about driving the highways of the Southwest is the incredible cloud formations and sunsets! If you take I-10 into L.A. don't miss the life-sized(!) dinosaur sculptures at Cabazon, CA (Exit 111, Verbinia Ave.) Although the Denny's, Burger King and motels detract from the effect, they're still a really cool sight.
That's a few thoughts that immediately come to mind. I'm sure others can offer more. Have a great trip!