Craig,
My first advice would be to tell your wife to hold on for a few more years.
In terms of jobs, a good paying job in the Maldonado area (involving taking a bus to Punta del Este daily, with a one hour or more commute each way) would pay you at best US$500 per month. In Piriapolis you would earn more in the US$300 region.
With children, and a decent lifestyle, you would be spending in the vicinity of US$2,000 if you kept things very frugal, or more like US$4,000 if you want to send them to a decent private school, for example. There is no way to make that kind of money unless you are an independent professional (lawyer, doctor, etc.) or run a very successful business here.
Opening your own business is something you never should attempt until you´ve been in a country for at least two years. Businesses in Uruguay in general are "scrape by" situations, so although a pharmacy could fulfill your goal of setting an example for your kids by going to work, down the line they could question your financial and business decision-making skills 
Lastly, beware of the relatives. You would be a rare exception if not approached by one, a few or a horde of in-laws downright attempting to borrow money for life-or-death (if you don´t lend) situations, or offering you brilliant business opportunities. You are and forever will be the gringo with the deep pockets in your family, and the earlier you learn to say no, the less money you will lose.
So, again, explain to her that it´s not such a great idea to return until the kids are a bit older, you don´t need to worry about your savings and you´ve researched your plans on the ground for a few years at least.
Visit Uruguay with an eye to living and doing business here, talk to all the °µÍø½ûÇøs you can (there are °µÍø½ûÇø groups meeting along the coast all the way from Colonia to Punta del Este), crunch "real" numbers collected during your research, and prepare the move thoroughly.