The A330 has an outstanding safety track record. As of March 2009, 600 A330s have been built (Wikipedia), as of now only 5 hulls have been lost (Aviation Safety). 2 hulls have been lost due to terrorism, 1 due to wrong declaration of dangerous cargo and 1 due to pilot error.

I would fly the A330 any time and with (almost) any airline. There is hardly any airplane around with a higher safety record.

More of concern is the usage of the airline. Which airline are you flying?