In my personal opinion I'd go with something bigger. 250 doesn't give you much oomph. Not saying you have to go real big but 500 ninja would probably be great.
However they say those bikes resell decent because people are always looking for them. I just don't buy something that costs that much and try to resell it in a year or two. But it's up to you. I think people make riding out to be a lot more difficult than it really is.
MAKE SURE YOU TAKE A SAFETY COURSE!!!!!! As a matter of fact safety courses in the US teach you how to ride. (Free in PA). Take one before you think about getting a bike, you may not even like it.
I totally agree...I just finished reading an older forum on beginner bikes that recommend starting with a 250, but I don't really get it. Although this may be true for some, I think that if you are a responsible rider, you can start with something bigger. I took the course using a 250 and when I got home I told my husband that I wanted to go out and buy a 250. He convinced me to take over his Honda Magna 750 instead because he felt that I would grow out of the 250 to soon and why spend the extra money. Considering he had been riding for 20 years, I took his advice.

Well, I spent a few days in a parking lot getting used to the 750 - did many figure 8s and after 2 years I moved on to a ~1600. This is all on a cruiser - whether the power/configuration of the sport bike changes things a bit, I don't know. Is it like having a Ferrari and not using it to it's potential?

For me, it all goes back to being responsible and riding within your own limits.