Neil Armstrong walking on the moon (Monday 21 Jul 1969 2 days after my birthday), I was 15 and helping move a new lounge suite into the lounge room, and we stopped to watch it on the old B&W telly.
Newcastle Earthquake (28 Dec 1989 wife's birthday) At a barby at the sister-in-law's place up in Toowoomba, and mum had just turned up by taxi and informed us she had just left the old man, and was coming back south to live with us...
Princess Di (Sunday 31 August 1997) Was driving into the dump, and the bloke on the gate told us, and everyone was stopped listening on their car radios.
The Twin Towers (11 Dec 2001), I woke up on the lounge in the early hours of the morning (fell asleep watching a movie), and saw the footage on TV and was trying to work out if it was a movie or something. Took a little while before it actually registered that it was real.