I definitely do NOT recommend the TTR225. I had one last year and it was WAY too heavy and underpowered. In addition, it only has a front disc brake and a drum rear brake. The suspension was not very good either.
A friend of mine has the TTR250 and I have ridden that. While still a heavy bike, it is much better than its counterpart the 225. It has both disc brakes, better suspension and of course, the e-button. For learning, this machine is quite forgiving and a fun bike to ride. I would stick with that.
Also, as Howard mentioned, the DRZ250 is also a good choice as is the XR250. They are all about the same bike, but the XR does not have the e-button and is about 20 pounds lighter.
Good luck and let us know what you get!!