Some Like It Hot - I wanna be loved by you
Greatest Showman
The Bodyguard - been done before I think but not loads
Moonstruck - That's Amore
also Gio and Michelle (but never used for movie week not sure why, the Cher look has been used many times, they have moon props. I love that movie btw)
Breakfast at Tiffany's - Moon River
also Sophie and Stacey used in general weeks
About a Boy - Killing Me Softly
difficulty to theme that as Hugh Grant never got with Toni Collette
Black Panther - Pray for Me
possibly you would want a pro and sleb of colour as it was a landmark movie Oti/Anthony Oti/Ugo are the only pairs I can think of /Black Panther was 2018
Breakfast Club - Don't You Forget About Me - They know the music as it has been used as a goodbye dance. What would Bender/Claire dance to it? Also as shown last night, red wigs = Cilla! 
Love Actually - Jump - PM/Natalie - Would she be dancing in a red coat?!
Big Lebowski - Just Dropped In - I would vote for a pj tripping Dude, aye
I agree there are other films to use though and/or other countries to nick from
Men in Black (still think Jojo and John should have used it)
I see fire (Hobbity rumba)
Boss Hoss Word Up couple's choice (Kingsman - just give me an eyepatch)
Pride - Shame, shame, shame
Mulan - Paso (hard to beat DWTS but a skirt reveal to red cape might work)
God forbid, Madagascar furries albeit we had Simon LeastWorstMemberOfBlue