We so amend 4x4times2 comments. In 2009 we made our first major trip to mainland Mexico. We could only count to ten. Our Spanish was basically limited to taco and tequila. The only sentence we could utter was one our daughter taught us: Donde esta bano?
We entered Mexico at Brownsville, TX and circumvented the country. We later termed this our "todo las playas (all the beaches)tour. We drove about 6000 miles and had absolutely no problems.
We did not understand the language or the money. Often times we just held out the pesos and they took what was fair. We don't think we were never cheated.
We're a couple of senior citizens. After we got home we ordered Rosetta Stone's Latin Spanish. We hadn't finished the first unit before we headed to Panama. Again, we made it to Panama and back with absolutely no problems.
Go for it!