I weigh about 190 and rode a 440. It was a very comfortable combination for me. It was an older bike so it was good to about 40 HP. As I progressed, I could have used a little bit more just for a little extra comfort.
So what the others said--- 250 is too small. My favorite all-purpose bike was the honda shadow 500 shaft drive. comfort, reliable, great on gas.
BUT, you need to learn first.
Before you buy one, take the MSF course. It's awesome. and it's fun. they'll provide everything you need--- bike, helmet, gas, and a course to learn on. you have to learn the right habits FIRST, before you start piling on miles. They teach on 125-250 typically, which is a preferred size to develop your skills on. If you pass the skills test at the end, you also get an insurance discount.
You also need to make good with whatever deity you believe in. Not saying that you WILL get hurt, but statistically most folks do, and you need to make sure you are comfortable with the risk. I packed it up after personally scraping a fellow rider off the ground in his last few minutes before dying. It rattled me, and my wife too much.
60 mile commute is not a beginner ride. until you tune your senses, habits, and develop your iron butt, that's quite a distance. You will fatigue mentally and also find that you dehydrate rapidly at that speed. Safety requires that you are fully alert, with active 360 degree perception. You kind of have to work up to it.
Statistically, however, you are safer if you DO commute on it, or at least ride not just on weekends. The weekend warriors do not get enough consistent seat time to nail down best-in-class habits. Clevy above sounds like he acquired the skills, and the /right/ skills, to be safe through the accumulation of many hours in the seat.... but most riders aren't consistent enough to develop that level of skill. (I applaud your accomplishment, Clevy, that's terrific!!!). Me personally, I rode weekends and evenings, and only to a carpool for work commute. My commute distance involved interstate and I just wasn't there. Rush hour could be a little nerve-wracking because people were tired, impatient, and worse in the summer, especially if they didn't have A/C. I rode a lot at night and in the evenings, little runs to the grocery. That was a more pleasant way to go but rush hour was the true application of awareness and mental test.
All the risks and fine print aside, there is nothing else like the feeling of riding. It thrills the senses. Smells, sounds, the feeling of flying, it is truly unique. Though I haven't ridden in years, I relive it every spring around this time whenever that warm, moist air with fresh "i'm growing" smells hits--- because it was springtime when I first started riding.
finding a group of riders is also a good idea. they can watch your line and give you pointers. unfortunately, not all of them are safe, not all practice good habits. But if you can find some that will show you how to group in traffic, how to hone your line, how to know when to stop and break, it can really help.
best of luck, be safe. don't just go buy something and jump on it. The national average time between bike purchase and first accident is: 18 seconds. (~2004-2005).
Mike