I have several email accounts that I can’t open but I would like to recover information from them – emails, addresses and contacts.
The below links might be helpful to you -
Recovering a lost or forgotten password [in case you know username]
Recovering or reactivating a deleted Yahoo account
well if you do ,not have access to the accounts then perhaps to contact yahoo for account recovery.
Yeah, this is your only bet. If everyone could get email from accounts they don't have the username/password for everyone could just open everyone's email, which would really suck.