Jason Alexander, aka George Costanza on “Seinfeld,” discussed before a packed house at Surflight Theatre in Beach Haven Saturday – with much humor and insight – his journey in show biz from being a 5-foot-3, 200-pound 12-year-old to a grandfather who directs on Broadway, teaches acting and has plentiful projects but can still spend time with his family.

In “A Conversation With Jason Alexander: The Artist Behind George Costanza,” as part of the Lighthouse International Film Festival on LBI, he…