We have exchange 2013 installed in Organization co-existence with 2007.

All the Mailboxes moved to Exchange 2013.

I need help regarding below things:

1- Mobile Phones Sync with exchange Successfully get emails and contacts but need to get Contact full information as configured in Active Directory.

2- If I rename the Exchange Server 2007 (also a Domain Controller), are there any complications.

1.  Are you asking about AD contacts or Outlook contacts?

2.  You cannot rename an Exchange server.  Remove Exchange first.