I just bought an 04 Limited Highlander 4WD. I don't really know the difference between 4WD and 4x4 if any. I know that it doesnt have the buttons to make it 4Low or 4High. So i guess what i am asking is if i got a suv that can go atleast to the sand. I take trips to San Felipe Mexico and it's mostly sand it's where they do the Baja 1000, if i go in to the sand with the Highlander will I risk getting stuck in the sand?

You bet, but you're going to take that risk regardless of the driveline. The 4x4 is much more rugged than an all-wheel drive. The Highlander isn't designed for off-roading and regular road tires aren't designed for trekking off in loose sand, either. If you're driving onto hard-packed sandy roads or gravelly surfaces you'll be all right, but don't go out on loose sandy areas like beaches and desert badlands. Areas like sugar-sand, beaches and loose sand provide no traction because the grains of sand are uniform in size and shape, and the sand itself will roll under your tires; that's what gets everything stuck. You need low ground-pressure treadless tires that have low air pressure in order to travel on that stuff, and even then you never know.
So if you DO go out on the sand and you do get stranded, don't blame the vehicle, just be cautious. Sand isn't friendly to vehicles for a whole lot of other reasons, too. Your best bet---rent a vehicle and take that out!