I wouldn't recommend a drop handlebar road bike for you, but there's a happy medium between that and a so-called comfort bike. You want to be comfortable on pleasure, recreational rides, but you also don't want to push a sluggish bike if you don't have to (remember that even on level ground, wind is just like riding uphill). I always say, whatever you want to ride, you may as well get all the performance you can out of the effort you put into it. What they would sell you as a "comfortable" bike would not usually be very comfortable for more than a few short miles. I would highly recommend staying away from Walmart and that kind of thing, and going to a real bike shop (or sports shop that has a big bike department) and start looking at some bikes they call "hybrids". These are bikes that are slightly more performance-oriented than cheap mountain bikes and comfort bikes. Still just as comfortable if not more, but better all round performance. These bikes can be reasonably efficient on paved surfaces (not in the same league as a real road bike, but way better than a comfort bike or even what they call an expedition bike), but you can also easily tackle established trails in the woods or wherever. You can basically ride these bikes just about anywhere. The advantage for you is that like the comfort bike, they have flat handlebars and they can be set high. Later, as you get more fit, you might want to have them a bit lower, and these bikes allow that.