holy hell i'm overwhelmed! PLEASE HELP!

[mupedalpusher]

I am 5'4 and ride a Trek 7.3 fx size 15 inch (mine is a regular frame not a WSD-womens specific design). A 17 inch bike may be too big but it depends on your proportions. I'm long legged but very short waisted for 5'4 so the mens frame fit me better at the time I bought mine. Along with my short waist comes very short arms so reach becomes a problem for me if I get a bike that is too big. You'll just have to get fit by your LBS to find out what works. We just bought a 13.5" WSD 7.2fx for our daughter who is 5'1, cost about $430 but is well worth it. If you can ride what you have and save more money, you'll have more options and get a bike that will work better for you.
I love my Trek 7.3fx and it has held up well, I've had it 3-4 years and commute on it (18-20 miles). She's a real workhorse and very comfortable.
Good luck and I'm so glad you are working toward a healthier life! You will love biking!