SAP EHP upgrade - Clarification

Dear All

We are planning to upgrade the our existing SAP system 6.0 on HP-UNIX and Oracle 10g. We are planning to upgrade to SAP ECC 6.0 EHP5. Request you to clarify the below points:

1. Is it require to test all existing customize and standard functionalities or only those which will be activated as part of EHP functionalities activation ?

2. What would be testing methodology ?

3. Does this upgrade change all objects like programs, tables, index etc ?

4. Can we upgrade directly from ECC6.0 to ECC 6.0.5 (EHP5) ?

5. Can I have all new functionalities module wise of EHP5 ?

Regards

Basis Head