Help! iPhoto/Mail failure to launch

I'm a photographer with all of my pictures in iPhoto. When I go to open my iPhoto (which is up to date) it gives me a message that says "the application iphoto/mail quit unexpectedly" and then says this in the report:

Process: iPhoto [255]

Path: /Applications/iPhoto.app/Contents/MacOS/iPhoto

Identifier: com.apple.iPhoto

Version: ??? (???)

Build Info: iPhotoProject-3780000~2

Code Type: X86 (Native)

Parent Process: launchd [99]

Interval Since Last Report: 225 sec

Crashes Since Last Report: 1

Per-App Interval Since Last Report: 0 sec

Per-App Crashes Since Last Report: 1

Date/Time: 2011-12-30 19:48:12.344 -0600

OS Version: Mac OS X 10.5.8 (9L31a)

Report Version: 6

Anonymous UUID: 3C3ED70B-175F-48F9-BC7C-AC08B67AB5B5

Exception Type: EXC_BREAKPOINT (SIGTRAP)

Exception Codes: 0x0000000000000002, 0x0000000000000000

Crashed Thread: 0

Dyld Error Message:

Library not loaded: /System/Library/PrivateFrameworks/iLifeMediaBrowser.framework/Versions/A/iLifeM ediaBrowser

Referenced from: /Applications/iPhoto.app/Contents/MacOS/iPhoto

Reason: no suitable image found. Did find:

/System/Library/PrivateFrameworks/iLifeMediaBrowser.framework/Versions/A/iLifeM ediaBrowser: unknown required load command 0x80000022

As soon as this gets fixed I will be backing up all of my photos on a hard drive I just wasn't able to before this happened. Any assistance would be greatly appreciated! Thank you!!