Usually the 1st thing to fail in a disk player is the transport (mechanism, laser) . I would put my money into a DAC rather than upgrading older player. You will have greater flexibility down the road with a DAC. When you need to replace the transport, this can be accomplished at less expense as you already have a good DAC.
I feed my Arcam DVD137 to a Bryston BDA-1 for CD and DVD playback. Direct to Pre for SACD. The DAC is also used for computer audio via USB/SPDIF conversion.
I feed my Arcam DVD137 to a Bryston BDA-1 for CD and DVD playback. Direct to Pre for SACD. The DAC is also used for computer audio via USB/SPDIF conversion.