Ehhh, would have to say NO. I have a Cel 433 with 64 Megs, but some DVD rips (DivX) won't even play without stuttering.
To play a dvdrip without any problems a Pentium III 500 (or similar) is required.
Note: some movies are played better than others. For instance i have American History X, which runs perfectly on my old pc (Pentium 166 with 40MB...)