I would say a Honda Pilot is a good bet. My BF has one, and fills it for $55, and gets about 350 miles to a tankful, and its a 4x4!!. Lots of space, and a smooth ride.
If you cant spend much tho, i would go with a Ford explorer, like a 2000 or so. Look for a v-6 one. Their are easy ways to get better gas mileage out of ANY car or truck.
Best ways i have found is to replace the air filter with a cold air intake, about $40 on ebay. This is a device that enlarges the pipe that the air to the engine is, and increases the cold air the engine needs.
Also, a tune up, including using the right grade oil, and using cleaners for the fuel injection and engine. The less gunk, the better fuel is burned. Also, check to make sure the fuel pump is in good working order, and changing the spark plugs and wires, to get a better fire and working engine. Also, using a gas additive helps extend gas mileage as well.
Pm me anytime with questions, and i will help
.. If you choose to go car, please stay AWAY from 4 cyl cars, they have alum heads and the WORST to work on!!