Hi there.
You need to understand that $250 really isn't going to get you a good quality
new bicycle. If you look around though, you might well be able to pick up a pretty good used bike on
eBay or elsewhere for that amount of money. You'd need to be sure that the bike wasn't stolen or worn out. Ideally, you would get somebody who knew what they were doing to check the bike over for you. It's also important that the bike fits you properly.
Do any of the bike shops in your area sell used bikes? Sometimes a shop will buy an old bike off someone as an inducement to sell them an expensive new bike and they will usually sell those bikes off pretty cheap. If it is a decent shop they would make sure that the bike fitted you and was in good working order.
If you have to buy new, accept that the bike will be heavy and made of cheap parts. If you really get into cycling then you'd want to buy a better bike at some point. If you get a year of two out of it then you've had a decent run for your money. Sell it for what you can get, or keep it for riding in bad weather when you don't want to take your new 'best' bike out.
One very strong piece of advice - don't buy a full-suspension mountain bike! One at that price will be extremely heavy and poorly made. If you are going to be riding only on the road, then don't buy any sort of mountain bike. A cheap road bike will ride a lot better than a cheap mountain bike.
PS One thing you could consider if you live somewhere flat is to buy a singlespeed bike. The reason being that you'd be saving the cost and weight of some expensive components. That would get you better quality parts, and there would be less to go wrong. Make sure you get one with a freewheel though. Since you are new to cycling, riding fixedwheel might be a bit risky!
This bike might be ideal for $229.95 + $39 delivery. You can flip the rear wheel round - one way is fixedwheel (you can't stop pedalling while the bike is moving!), the other has a freewheel (you can!).
If you have big hills to ride, then a singlespeed bike isn't going to be much good for you unless you are already super-fit.
