Paramount isn’t going to release figures for Thursday night’s 8 p.m. showing of “Iron Man” until Sunday night, but Steve Masonreports that other studios are estimating a take of between $4.5 million and $5.5 million for the “preview” screening at more than 4,000 venues. While “Spider-Man 3,” “Pirates of the Carribean: At World’s End” and “Transformers” all took in over $8 million during their first shows last summer, the “Iron Man” numbers would seem to predict it will still pass the $100 million mark by Sunday night. That would make it the second-best nonsequel after the original Spidey stunned the business with a $114 million opening in 2002.