Starting in safe mode

While the XP and Vista operating systems don't crash nearly as much as their predecessors, they still freeze from time to time. More commonly, a particular program refuses to work the way it should. The first line of attack is to simply restart (reboot) the computer, and most often that solves the problem (which in that case probably was to do with fragmented memory, or a conflict between two pieces of software). If that doesn't work, the next option is to reboot in "safe mode". This is a bare-bones working mode that disables all extensions, including printer drivers, internet, etc, and is a good mode in which to do trouble-shooting. Oftentimes, simply starting in safe mode and then rebooting in normal mode without doing anything else solves the problem. To reboot in safe mode, hold down the F8 key at the top of your keyboard while starting the computer. You will get some beeps, and the screen will show only black with white writing. At some point, it will stop and offer you three choices to continue. One of these is the safe mode, and you use the arrow keys at the right of your keyboard to choose this, and then press "Enter" to continue. When the computer is in safe mode, the screen operates at a lower resolution, which means all your icons will be bigger, and when you restart in normal mode, you will have the fun job of resorting all the icons.
Some people have difficulty with Firefox freezing, which may be caused by conflict between extensions and add-ons. You can also start Firefox in safe mode, which disables the extensions, and you can then turn them on one by one, to find out which is the culprit. You will find the safe mode by going to Start/Programs/Mozilla Firefox.