Defending against them isn't really an option. The only question such tactics raise is how long it'll take them to score.
I'd rather we played our usualy game, which of course means keeping it tight at the back as well, but our strength lies in our attack and midfield this season, which works perfectly as their defence is terrible.
We should play our usual game and try to take something from the match. If we lose, then at least we gave it a bash.
Points against the Old Firm, especially on their own patch, are always a bonus rather than to be expected.