NEW YORK — Veteran helmer John Schlesinger is in talks to direct Rupert Everett and Madonna in “The Next Best Thing” for Lakeshore Ent. and Paramount, sources said.Scripted by Tom Ropelewski, the film is described as a biting comedy about best friends — one a straight woman (Madonna), the other a gay man (Everett) — who decide to have a child together. Cut to five years later when the woman falls in love with a straight guy, wants to move away with the child and a nasty custody battle ensues. The film is expected to get under way in January and is produced by Lakeshore’s Tom Rosenberg, Leslie Dixon and Linne Radmin. Schlesinger’s repped by UTA.