No there is no difference in character between the connection and the connexion. And I'm almost positive you can't debug the original 1996 (i think that was the year) tamagotchis, the ones without infra-red connection, those yeah you can't debug those.
Uh, from what I read, Connection is North American, and Connextion is European...so depending on where you live might help =P. If you're thinking of V1 and V2, then definitely get V2.