1=> u need 2 give both group for merit list.
2=> u can not give Both Groups until unless u Register for both Groups.so in ur Case u can give Only Group1.
3=>Orientation Course is 35 Hours Course Conducted by ICAI for Developoment of communication skill & personal skill ( its including Group Discussion,Presentation etc)
4=> First Of all u need to Complete 100 Hrs ITT Course for getting eligible for IPCC exam & u can complete ur Orientation Course after ur attempt but u shoud complete it before date of Result Declaration of IPCC exam ( Otherwise ICAI will hold ur result till completion of Orientation Course)
5=> NO, If ur cleared Atleast IPCC Group1 then only u will be eligible for articleship.....
I Hope u got the Point.....
Pl Revert Back if still u have any Query.....