Cozumel, Cancun, etc. we're developed by the Mexican government to attract tourists. They are by definition "tourist areas". Not that this is necessarily a bad thing. But they do not reflect true Mexico in many ways.Â
Mexico is a varied country from one place to the next, and you need to simply rent a place for a few months and then use this as a base for exploring the rest of the country. I have traveled all over Mexico in the past 30 years or so and I favor the central highlands. Spring like weather almost year round, high and dry means no mosquitoes. Do pick up some basic Spanish.....it isn't essential but will make your stay easier and more interesting.
If I were going to move there permanently, here is my short list:
San Miguel de Allende
Guanajuato (the city in the state of the same name)
Puebla
And if you like a more indigenous culture, San Cristobal de las Casas........this one is in he southernmost state and only about 4 hours from Guatamala.Â
At any rate, do yourself a big favor and travel before making a permanent selection. The buses are terrific and go pretty much everywhere. No comparison to the Greyhound buses in the states.
In all of the years I have traveled around Mexico it has been mostly by bus, and occasionally by personal vehicle. I am a little more adventurous than you, maybe...I have driven my own auto all the way to the Guatamalan border.Â
If you decide to cross from Texas, here's what I generally have done for years:
Drive to Laredo, TX and locate the Greyhound station. They have a multistory parking garage. Park there, and walk several blocks to the border bridge. Cross over on foot and do the paperwork, then hail a cab to the bus station, which is several miles away. Purchase a ticket to your destination. Always ride the first class buses. Carry a sweater as the air conditioning can be a little too cold at times. The buses tend to arrive in he mornings and leave in the evenings, but major routes may have a bus or two leaving in the morning. Plan on arriving at he station before noon, or you may find the seats all sold out and you will have to camp out in the lobby or find a room untill the next morning.
Well, I am running on here. If you have any specific questions I would be happy to answer them. However, I have never in all my years of travel there been to Cozumel or Cancun. I prefer to dodge the tourist Meccas.