Officially (i.e. according to the US embassy website) you're ineligible to use the Visa Waiver Program. However:
1) the form you complete on the plane doesn't ask about arrests. It only asks about convictions for crimes of 'moral turpitude'. You can honestly answer 'No' to the relevant question ;
2) the US immigration service have no direct access to UK criminal records (or to records of arrests), so they won't know about your brush with the law (unless, possibly, you were arrested on suspicion of plotting a terrorist offence against the USA!) ;
3) you'd never get a visa in time anyway. According to recent posts you wouldn't even be able to book an interview until around the end of June.
As Sddsddean suggests, just use the visa waiver scheme.
Chris