For years I had taught people how to do screen captures with the Print Screen button and continued to be mildly surprised when people who get excited when they learned that there was actually a purpose for tha button on the keyboard! I still use that when I am not at my own computer.
Since I have to do some faculty development sessions, training medical educators on use of technology in education, I had to find some tools that were easier to use. So here is my very short list of 3 applications that I find very useful.
1. Jing - This is a great tool for capturing a portion of the screen and annotating it with arrows and text. While it does do screencasting, the free version has limits on time of a single movie and it puts its logo prominently at the end of the movie. It also allows to upload the captured image to its online repository. I do not use that much as I need to save and reuse the images for other purposes.
2. Wink - After a lot of trials and errors, I have settled on Wink for screencasting. It creates a flash movie from a window that you select on your screen. You select the number of frames/sec and it will capture these faithfully. It has a builtin annotation tool for adding callouts, textboxes etc. Also automatically adds pauses to the movie and you can add navigation buttons for the user so they can read the text and then proceed with the movie. You can delete unnecessary frames and thus keep the movie short and sweet. The only problem I had was deciding on the resolution. I used the Firefox window resizer add-on and captured at 800X600 so I could put the flash file in a frame or otherwise have room left on either side.
3. FRAPS - this is the only one of the 3 that I spent money on (35 dollars). I use Second Life for various educational purposes and FRAPS allows me to record the machinima in SL - both audio and video. It is very easy to use and has a hot key to start, stop the recording. The only thing to keep in mind is the incredibly HUGE file size. For one 20 minute recording it used up 10 GB of space on my HD. The solution is to use Virtual Dub to compress this to MPEG4 and the same file become close to 400 MB.
So that's it! Jing, Wink and FRAPS.