Here is a very good article on bug reporting, discovered by Atmasamarpan:
http://www.chiark.greenend.org.uk/~sgtatham/bugs.html
It certainly helped me sympathise with poor developers and curb my linguistic excesses when reporting problems.
Whenever possible, screenshots really help to pinpoint the problem by making the developer or Plone admin see what you’re seeing. Below are some instructions for screenshots for both Windows and Mac…..
1. Windows
You can capture the screen and paste it into any graphics program: by pressing the ‘print screen button’ (up there somewhere to the right of F12). This appears to do nothing when you press it, but the screen is then stored in memory. One can then open any graphics program like Photoshop or even Microsoft Paint and paste in the image. (For Photoshop one should first create a new document)
If you dont want to save the whole screen, pressing ‘Alt’ and ‘Print Screen’ together will capture only the window you have open.
This is a slightly clumsy way to do it; there are freeware programs out there which do the job much quicker (and which personally I’m happy enough with, for example MWSnap) but I understand the words ‘windows’ + ‘freeware’ together can be enough to send a chill up the stoutest of spines……
2. Mac
The keyboard shortcuts are:
Both options automatically create an image for you named "Picture 1.png" on your desktop.
There is also an application named "Grab" in the Utilities folder which allows screen captures with more options. Grabs features can also be accessed from the "File" menu within the application Preview.
Further in-depth information on screen captures in Mac OSX 10.4 can be found here: http://www.macworld.com/weblogs/macgems/2005/09/tigerscreenshots/index.php
(thanks to John-Paul for the info)