Here's some notes on using GIMP... some of them are specific to the Windows port of GIMP.  In case you didn't know, GIMP is the GNU Image Manipulation Program.  Some call GIMP a Photoshop killer... for the vast majority of people, Photoshop offers nothing they need that GIMP cannot supply.  Oh, and Photoshop is $600, but GIMP is free

Where is everything???	Right-click on the image you're editing.
How do I undo something?	Press CRTL + Z
How do I make a menu go away?	Press the ESC key.
How do I draw a straight line?	Choose a drawing tool, click the starting point for your line, hold SHIFT, then click where you want the end of the line.  [ more ]
Zoom?	Use the - and = keys.
I want the window to resize when I zoom.	File, Preferences, Interface, Image Windows.
Rotate?	Right-click the image and choose Select, None, then right-click the image and choose Image, Transforms, Rotate.
Resize?	Right-click the image and choose Image, Scale Image.  The long button next to Height lets you choose pixels, percent, inches, etc. The small button under that one, the button that looks like a chain, lets you lock the perspective of the image, so that if you make it 50% wider, it will also be 50% taller.
Crop?	Right-click the image and choose Tools,Transform Tools,Crop and Resize. Then drag the mouse over the part you want to crop, and click Crop.
Browse a folder of images?	In GIMP's main (tool) window, choose Xtns, Guash.  Find the file you want and click it once to select it, then again to open it in GIMP.
How do I set ("bind") keyboard keys for menu items?	Go to the menu selection you are interested in. Keeping it selected (hold the mouse's menu selection down if necessary), press the key sequence you wish to assign to the menu. It will appear on the right of the menu. The new binding will be saved and used in future GIMP sessions.
Where can I learn more?	tutorial: http://wingimpfaq.cjb.net tutorial: http://gimp-savvy.com/BOOK/index.html  tutorials: http://www.gimp.org/docs.html
Printing info...	The GIMP's Windows print plug-in prints an image (just the active layer, actually, so make sure to flatten the image before printing) in its natural size, so to adjust the size of the image on paper use the Image:Scale:Print Size & Display Unit dialog. (This doesn't change the image pixels in any way, just its logical size.) In order to look at an image on the monitor at its natural size, measure your monitor's size, set the pixels-per-inch (or pixels-per-millimeter) value in the File:Preferences:Monitor dialog, and uncheck the Dot-for-dot entry in the image's View menu. [ source ]
Windows 2000 installation info...	I figured out what the problem is with running GIMP on my Win2000 box. There are glib, gtk, gdk files placed in your Program Files\Common Files folder, but there are also some placed in your WINNT\system32 folder. On my system, the ones in the system32 folder were causing trouble. I renamed them (for example, glib-1.3.dll to glib-1.3(bad).dll), and then Windows uses the ones in the Common Files folder. Then GIMP starts up just fine.