Continuing a theme from last week's Snipping Tool, if you're working in Word 2010 you can directly insert screen captures into a document - something else I had to have pointed out to me (by my wife, in this instance). Short and sweet and oh so useful: ICT Tip 046 - Insert Screenshot in Word.doc
Late again. Sorry!
This one was new to me when a teacher pointed it out, and is actually fantastically useful - particularly if you're trying to train your users in how to report an issue (good luck, if so). ICT Tip 045 - Snipping Tool.doc is an easy way of screencapping areas of a screen. It is actually quicker than Print Screen -> Open Irfanview -> Paste -> Crop -> Copy -> Paste, so may well be useful to you as well as your end users.