You are gathering information to help you know what to. . . search for. Your first road bike is a big step. No matter your size there are some guidelines to follow for your first bike!
You want to make sure you get a bike which will provide you with a good platform to start from. You also don't want to break the bank get this new bike either. You will probably find once you start riding you really enjoy it. You are not alone most people do!
So to make sure you are happy with your bike for a longer period of time it is best to steer clear of hybrids. Not that there is anything wrong with hybrids. . . . they just make upgrading more costly.
The best thing for you to do is start out looking at a lower end road bike. Start looking at something which has shimano 105 components. You can even take a step down and use shimano Tiagra components. These are great components to start out with. When you decide to upgrade it will make it cheaper for you by starting here. . . at the very least.
One thing to realize is road bikes can feel stiffer when you first ride them. You will get use to it and appreciate it later. A road bike gives you more positions for your hands than say. . . . a hybrid. Your hands and arms are less likely to feel sore with more hand positions to choose from. You will come to appreciate a variety of hand holds on your bike! The particular brand of bike is not nearly as important as the particular comfort level it gives you.
You will probably notice some differences in the stiffness of different bikes. So find one you feel most comfortable on. For your first bike don't be embarrassed to ask for a previous model year or a. . . . used one. It will save you upwards to several hundred dollars by doing so. Now you have a starting point and an idea of what to look for!
See you on the street!
For more information on entry level road bikes and for some recommendations go to: http://www.mycyclingsource.com/entry-level-road-bike.html