What's the best way to backup a LARGE iPhoto 9 library

So, as the title states I currently have 29,713 photos in my library, and I'm looking for the best solutions for backing up. In the past I have just dragged my libray over the EHD and moved on. I have read stories of upgrading iphoto and how some have lost photos or they just don't transfer over. I'm really looking to upgrade anytime soon but I'm wanting a solid plan that I can count on. Before we switched to digital I used to have all my film pic's copied to CD's for backup so I have those, but since then I just import my digital photos to iphoto and erase the camera disk. I realize I'm living on borrowed time since it's not IF my HDD with fail...it's When!

So my questions are....

1.) Do I just continue backing up the library as in the past?

2.) Is it wise to backup the "Originals" folder in my library?

3.) How would I go about doing #2 without screwing up my current library

4.) Do you guys trust online backups like Carbonite etc...

Thanks for your help!

Eric