Yep! You are right Rajeev,

1 is not an option of OPS, but Standby or like IBM HACMP failover configuration which we have in our shop.

2 is the right option and by definition it is OPS. Multi nodes(instances) accessing one set of datafiles.

I do have little knowledge on it as we planned to implement it, but we never did. We bought even box to implement OPS and again Management changed their mind and switched over to HACMP to minimise maintenance effort of OPS.

Hope this helps.