Reasonable on 24 June 2009
I did same thing recently. Use the backup utility and everything will be backed up on your HDD. Annoyingly, due to the new HDD once you've installed and formatted it, when you restore from the external HDD your PS3 will restore users, saves, wallpaper, themes, etc. but will not restore any PSN games, etc. as they will be 'locked' to the old HDD ID.
You will therefore need to re-install the games from PSN. I understand why the do this from a piracy point of view, but it is a bit of a pain.
Try to be reasonable... its easier than you think...
