Teenpop Public-Domain Brit Lit would be a good added day (and covers every suggestion that feels like it would widen the scope too much, like Easy A). I'm assuming Allan Moyle is too alt and for the wrong generation. And Mean Girls must be the opening night gala screening. Besides that: High School Musical 3.
Would that include 10 Things I Hate About You and anything else vaguely based on Shakespeare? Because that would mean Romeo + Juliet is the opening film, obvs.
EDIT:HSM doesn’t make an appearance, but I would be willing to show the karaoke version if there was audience participation. Would be on the first night.