LogFAQs > #976904337

Even though the Otacon Ending is non-canon I think it's better and should be done on your first playthrough.

Here's the comparison if you forgot

*obviously MGS1 spoilers >_>*

Otacon Ending:
https://www.youtube.com/watch?v=d1nwsRZycp8
Post-jeep ride part:
https://youtu.be/d1nwsRZycp8?t=1083

Meryl Ending:
https://www.youtube.com/watch?v=qKFEVRnP6Sc
Post-jeep ride part:
https://youtu.be/qKFEVRnP6Sc?t=1104

Otacon's ending is more about accepting others and living life to the fullest even with the loss of loved ones. Meryl's is just "I wanted to see you Snake! Let's journey together in life. Oh look, there's some caribou" >_> Psssh!