I' d second cyclocross bikes as a good all rounder. Take a look at the surly cross-check as it is more versatile than most and can handle some trails. Touring bikes also make good all round bikes and tend to have be more clyde friendly from the start. Jamis bikes are pretty good bang for the buck. Find a good dealer and try it multiple times before you buy, fit is hugely important. If you're just starting out with drop bars, set them higher than the saddle and don't let them set up a low drop position initially. You can lower a stem but it's harder to fix a steerer tube that is cut too low.
But make sure you feel comfortable with what the shop is telling you. If not, go somewhere you are comfortable. A good shop will help with so many things, but there are many shops that can't or won't be helpful. In my area, there are six shops, only one gets my repeat business. The good ones try to build a longterm relationship with you. Rei tends to carry or be able to order some decent bikes, but their service departments often leave something to be desired.
Look into cycling groups in your area or your state gov webpage, they'll probably. Have info on your local laws, routes to ride, maybe even basic cycling skills classes.
As far as gear goes, start with the bike and a water bottle. You don't need Lycra and not right away if you decide you do want it. I favor wool, some ride in lycra, some in everyday clothes. See what works for you. If you decide to ride to work or school you'll have different needs than if you ride recreationally. So ride and see how you want to ride before investing in stuff you may or may not use.