ONGC is Indian oil and gas. It is a relative bargain because of the Asia play and the fact that the sales are mainly an effort to hide the red ink that the Indian government is making this year (desperate sellers induce bargains - duh).
Buffett would be smart to take advantage of such a deal; it is right up his alley.
IT IS NOT - however - a play for oil and gas. While the state run firm (now moving towards being privatized) does do oil and gas distribution and has limited capabilities in exploration its main money maker is the distribution and such.
It's more a play on India and Asia in general than anything else.