Great work from Dicaprio, De Niro, and especially Streep certainly make the film watchable, but it still can't save it from feeling like a TV movie of the week. If you're a fan of melodrama... and over 60, then you'll find much to like.
Based on a play by Scott McPherson's who died of AIDS, it's impossible to watch the well-acted film (particularly Diane Keaton, who should get an Oscar nod) without thinking of its themees: the various approaches to love and the strength of family bonds
There is a core of substance in Marvin's Room, and persuasive acting to back it up. Which makes it a special pity that the filmmakers didn't trust viewers to have the necessary intelligence to figure that out for themselves.