The website of the US embassy states that anyone who has ever been arrested (even if totally innocent) or convicted of any offence is ineligible to enter the USA under the Visa Waiver Program. So (officially) you must apply for a visa. It can be a lengthy process. (I've seen a post, here on AB, from someone who waited 6 months for a decision, only to be turned down).
However, the US authorities have no direct access to UK criminal records. US immigration staff will know about specific individuals, where the UK has passed on information, such as suspected terrorists, drug-traffickers and child-sex tourists. They won't know about the vast majority of offences committed in the UK. So, if you simply lie on the form, which you complete on the plane, you should have no problems entering the USA.
Chris