Welcome to TE! My first suggestion would be to take ones self to the bike shop in your town, you'll want to ride many bikes, hopefully there will be some really cool folks there. They should make you feel at home and not stupid or ashamed to ask any question what so ever. The guys at my shop have been around bikes for so many years they could help you by looking at you ride and start narrowing down the vast options so you won't feel overwhelmed. Sadly, not all of your bike shops are created equal, it took some time and frustrations to find the right shop so good luck to you!!

The bike shop folks (as will we) will ask questions like what type of riding will you be doing? Dirt paths, pavement, gravel? Do you have any goals beyond riding more and fitness? As to bike sizes, there are many major manufactures out there that make bikes for smaller women and 5'3" is not all THAT small for a girl. There are many members here in your size range or even smaller.

Good luck in your search and let us know how things go!

Shannon