Welcome to the site :cool:
Be sure and go to your User CP and update information relating to your location, type of riding, etc. After that grab a spot on the couch and tell us a bit about yourself. How long you have been riding, what kind of riding you prefer, where you are located, etc. We will do our best to hook you up with some fellow dirt bike enthusiasts.
Before you purchase a bike, check out the
What Bike Do I Get... ? forum for great information on what dirtbikes might suit your needs and desires. There is a great group of folks that hang out in there always willing to help a newbie to the sport. Dave and Gomer are on target, the TTR is too small. My daughter does rides one as a rank beginner with maybe a couple of hours of total time on it to date. She will completey outgrow it when the day comes that she spend one full day on the bike. BTW - she is approximately your size.
Also, the TTR is a completely different bike than the other bikes you mention.
Again, welcome to the site and shout if you have any questions! We are always willing to talk bikes!!