Can use another account instead of 'sa' ?

Can I change the MS SQL account from sa to another account while change the database. I've got the concern from my customer that the 'sa' account is not secure enough and break their IT security policy. I've try to changer to another account let's say 'servicedesk' but after I restart the server the servicedesk plus service is starting for a while and not response (as in the attachment)

Regards,