Cannot open iPhoto, freezes when opening after updating

Hi there,

I am now using iPhoto (newest version) on my Air (Mid 2009, Intel, 2.1 GHz, 2G RAM, SSD).

Last week, cannot remember whether Thu. or Fri., the system software update alerted me for new updates, in which, there was this new update for iPhoto. I clicked update and it automatically did all the stuff just like always. And the day before yesterday when I clicked iPhoto icon, an update window shew up and everything stopped on "Step 5" with the progression bar on 99%.

The wheel is running, the windows are still movable. The CPU indicator shows that the CPU is still running. The desktop I run iPhoto is also frozen but other desktops (I guess you know what I am talking about multiple desktops) are OK for use. I thought it might take a long time so I leave it there, and it is still the same after 2 hours.

I included a screen shot below.

HELP!!!!!!

all my thanks,

Frank