You're only an hour away?? Lucky! There are a couple of very shallow shore dives where I live within half an hour but if I want to get on a boat it is over 1.5 hours (or if there is a long weekend and traffic can be well over 2). Fair enough there is a local store to me, but even if there wasn't I still have to drive hours to even get to the dive site so wouldn't make a difference to my diving anyway.
I have never run a dive shop or anything diving related (a noob to the sport actually) but I do run my own business and so does my partner so I have a fair idea of what it takes to run a business. You haven't put much in your profile but I am basing my next comments on your OP (apologies if they aren't good assumptions but there is not much to go on) - if you were OW certified in 2005 and have not dived since, chances are you are not a very experienced diver at all and very out of practice. Therefore I doubt you will have much knowledge about gear, diving sites, and other general diving info and I know personally I would not take advice from stores where the sales people didn't know about the above. If you go into business, you have to know the industry if you want to be successful. And that is no guarantee of success either.
Also, if you want to own the store so you can dive more often, you can't stop diving for years because of an hour long trip... I mean you are wanting to set up your own store versus driving an hour! If it were me I would take the hour trip as the effort of running your own business is monumental at times, especially the diving industry I would imagine. I am guessing a lot of stores would not be doing great at the moment due to a poor economy in a lot of places and also internet stores that can sell gear a lot cheaper than many LDSs.
Also, I used to be an accountant, where one of my roles was setting up businesses for people and looking into insurance and the like. An internet forum is the last place I would be going to get advice like that. Fair enough many people are knowledgeable here but you are going to have a spend a fair bit working out stuff like that with insurers, accountants, lawyers, etc.