THE one thing that sticks with you about Kate Capshaw’s – that is, Mrs. Steven Spielberg’s – drowsy vanity project “The Love Letter” is its bizarre attempt to pass off Blythe Danner as Capshaw’s mother. Hel-lo! There’s only 10 years difference in their ages. Dame Spielberg, 45, is a lovely woman, but why didn’t someone point out to her that she, too, is old enough to be Gwyneth Paltrow’s mother – and looks it?

If “The Love Letter” were set in an Arkansas trailer park, this might make sense. But its setting is a picturesque New England coastal village called Loblolly-by-the-Sea (think Garrison Keillor meets Martha Stewart).

How picturesque, how quirky, how postcard-perfect is it? The beefy fireman George (Tom Selleck) loves opera. The town biddy, Miss Scattergoods (Geraldine McEwan), putters about on her bicycle making flinty observations.

Yes, if this eccentric burg were a farm, you’d call it Pepperidge.

It even has a “You’ve Got Mail”-ish bookstore that no paying customers ever seem to visit but even so makes enough money to afford a staff of three.

They all labor for owner Helen (Capshaw), a divorcee who runs on the beach to work off the frustration of never having a date.

“The Love Letter’s” MacGuffin makes its entrance when Helen discovers an anonymous amorous epistle between the cushions of a sofa. She thinks it’s a mash note from thick-headed but sexy Johnny (Tom Everett Scott), the hunky college student working in the bookshop during the summer.

When Johnny sneaks a secret peek at the letter, he assumes Helen wrote it to him. They smolder, they grope, but farce never once threatens to break out.

Meanwhile, George continues his fruitless crusade to interest Helen in age-appropriate dating. That infernal letter causes more problems when, out of the blue, Helen’s sexy mother (Danner) and dotty grandmother (Gloria Stuart) turn up abruptly for mysterious, letter-related reasons.

There’s no lightness or magic in any of this, and I think the problem is mainly Capshaw. Her Helen is cold and charmless, all sculpted body and aloof hardness. We need to sense that underneath that forbiddingly firm shell there’s a soft, gooey core just waiting to come gushing out. But the most that can be said for Helen is that she’s in great shape for someone her age.

Believe it or not, Ellen DeGeneres is easily the best thing about this depressing picture. She plays Janet, the bookshop’s business manager, and though she too complains that no man will look at her, Janet is the one female character who seems to have a sense of humor.