Google is probably your best resource for these questions. But briefly:
what is Spring
Spring is an application framework based. It was born out of the perceived failings of large J2EE application servers to provide a mechanism to offer simmilar functionality without the need to depart too much from a programming model most programmers will understand. So no "magic" components like EJBs for example.
what is ... Hibernate Framework
Hibernate is a persistance framework. It is an abstraction layer between the domain model of your application and the relational data model of your database.