What is a "British" film?
This can be defined in 2 ways:
The British film industry as a vertically integrated structure (ie, the studios being responsible for the entire film-making process) hasn't existed in Britain since the 1970's.
Today, financing largely comes from outside the UK, mostly from the US and Europe. Distribution and exhibition companies are dominated by US companies, ensuring UK productions take precedence in the American film circuits.
As a cultural institution, the focus is on the representation of "Britishness" and British culture in films, and what part those films play in depicting and projecting an image of the nation. Also taken into account is the contribution made by these films to the forging of a national identity and culture; this has been especially demonstrated with such films as Bend It Like Beckham and Anita And Me.
Other British genres that have represented British culture at different points in history include the Ealing comedies (in the form of costume melodramas), realist wartime films, realist "kitchen sink" style films (from the Free Cinema movement) and not forgetting the James Bond movies, especially during the 1960's.
These genres and movements that constitute 100 years of British cinema have helped to portray Britain in all it's regional national and cultural diversity, forging a multifaceted identity for Britain, which is at variance with the more one-dimensional stereotypes to be found in Hollywood films.
The cultural content may also define a "british" film through it's iconography (visual codes such as props, settings/location, costume) and speech (accent/dialect, ie. regional or "BBC" English). Such elements serve to identify a film as "typically British".
For example: Bridget Jones's Diary (Sharon Maguire, 2001). This film has a mainly British cast, except for the titular Bridget played by Rene Zellweger, with the stereotypes of the ditzy thirtysomething and the stiff upper class British male, which obviously appeal to modern day American audiences (the fact that the main character is played by an American with an English accent increases the appeal).
If you want to get technical about it, the 1927 Cinematograph Films Act states that a quota of British films would be shown at UK cinemas during a time when Hollywood dominance was such that less than 5% of films shown were British. This need for a quota of British films ended in 1982.
As a result, criteria were laid down as to what classified a "British" film, although these criteria have changed over the years. In modern British cinema today, whether a film is "British" depends on the following-
a) production personnel (ie. director, producer, studio)
b) source of finance for the film.
Examples:
Brassed Off, Trainspotting: these can be classified as "british" cince the cultural impetus and financial backing comes from the UK and the production companies are British.
Goldeneye (no.17 in the James Bond canon ): even though the UK has creative (British director, crew and is filmed in England) and part financial involvement, is financed largely with American money.