You will get an entry level bike for $250.00 - period. There are decent entry level bikes in that price range, but it is still entry level which means that it will not be nearly the quality of a 'good' bike.
The Replica is cool or the DK Cincinatti is cool. There are others, but ask before you buy and get your heart set on something.
Also, weight should not be an issue. If you want a good lightweight street bike, then you are confused about what sport you are in.
Freestyle bikes MUST be strong or they fall apart really quick. So, almost every bike - from the top of the line pro bikes, to the cheaper bikes, will all be between 30 and 35 pounds. Some really lightweight ones are around 28/29 pounds, but then they are sacrificing strength to get to that point.