I found this bug on a Windows 2000 (Service pack 3) system using the latest 
build (643C) of Open Office. Steps for replicating the bug are:

1) Create a new OOo text document.

2) Using Insert-->FloatingFrame menu, bring up the 'Floating Frame Properties' 
dialog box.

3) In the "Name" field of the above dialog box, give any name and in 
the "Contents" field, provide the path of any image (JPEG) file (in my case the 
path was like 'file:///C:/Documents and Settings/rvemuri/My Documents/My 
Pictures/Sample.jpg') and click 'Ok' on the dialog box.

4) As we can see a floating frame with the image is created in the document. 
Now click on the image and try to edit the RGB(Red,Green,Blue) colors of the 
image. More specifically, after selecting the image, try to use the list menu 
for the 'red' color and try to decrement it.

5) The open office crashes or hangs indeterminately.

          I think it's definitely a major bug considering the fact that the 
user might want to edit an image inside a floating frame and hence worth 
reporting.