Wal-Mart's (WMT +0.3) plan to offer a service to convert DVDs into the online access to movies will launch April 16 in close to 3.5K stores. For $2 customers can watch a standard-definition copy of a movie, while a high-definition version will run $5. The big question for Wal-Mart and new rival Netflix (NFLX +0.1%): Will customers prefer to own digital rights to a movie for $2-$5 or stream movies for $8 a month and watch them once?