Twin big-ticket openings of “Charlie and the Chocolate Factory” and “Wedding Crashers” aim to keep the box office hot for a second straight weekend. Warner Bros. is releasing the family film starring Johnny Depp at 3,770 theaters while New Line is taking the Owen Wilson-Vince Vaughn R-rated comedy out at 2,925. With “Charlie” expected to open near the same level as last weekend’s $56 million bow for 20th Century Fox’s “Fantastic Four,” and “Crashers” expected to deliver impressive numbers as well, the weekend box office is likely to run ahead of the same frame in 2004, when Fox bowed “I, Robot” to $52.2 million. Tracking on “Charlie” has been surging in its final week before release, with interest strong from both family audiences as well as the adults fond of the 1971 original. Only obstacle potentially in “Charlie’s” way may be the latest “Harry Potter” tome, which will go on sale Saturday. But Warners hopes the young fans of “Potter” will have no trouble finding time to consume “Chocolate,” too.