I'd expect people to have seen many of these:

10 Rillington Place – Richard Attenborough as serial killer and necrophile.

Abominable Dr. Phibes, The – Vincent Price camp classic

And Now for Something Completely Different – Monty Python sketches

Anderson Tapes, The – Connery robbery while being watched

Andromeda Strain, The – Michael Crichton adaptation

Bedknobs and Broomsticks – Disney mix of live action and animation

Beguiled, The – Clint Eastwood gets interesting #1

Carnal Knowledge – Mike Nicholls directs Nicholson

Clockwork Orange, A – Kubrick masterpiece

Devils, The – Ken Russell goes mad

Diamonds Are Forever – my favourite Bond

Dirty Harry – Clint Eastwood shoots people

Duel – Spielberg's breakthrough

Fiddler on the Roof – Topol musical

French Connection, The – with the best car chase, ever

Get Carter – One of Michael Caine's finest

Growing Up: A New Approach to Sex Education, No. 1 – Martin Cole shows real live sex

Harold and Maude – he's obsessed with death, she's dying

Johnny Wadd – John Holmes + plot: why Boogie Nights was made

Kidnapped – Michael Caine does a decent Stevenson adaptation

Klute – Donald Sutherland + Jane Fonda

Last Picture Show, The – Bogdanovich's best

Le Mans – Steve McQueen + cars

Mary, Queen of Scots – Vanessa Redgrave & Glenda Jackson

Morte a Venezia – aka Death in Venice

Pink Narcissus – gay classic

Play Misty for Me – Clint Eastwood gets interesting #2

Rouge aux lèvres, Le – aka Daughters of Darkness, classic lesbian vampire

Shaft – John Shaft!

Sunday Bloody Sunday – Jackson again, bi classic

THX 1138 – When Lucas could do plots

Trafic – Monsieur Hulot

Tragedy of Macbeth, The – Polanski's version

Unman, Wittering and Zigo – aren't British public schools great.. for murder.

Up Pompeii – film version of titterful UK TV sitcom

Willy Wonka & the Chocolate Factory – the original

(The only two I haven't seen – but would pay to do so – are Johnny Wadd and the Martin Cole sex ed. All the rest are worth watching.)

But none of these was apparently #1 at the UK box office that year.

What do you think was?

(Update: and even if you don't want to guess, how many have you seen?)