The standard system font size in Windows XP is 96 dpi. You can also use 120 dpi, if your prefer bigger fonts or you can set this font size to your own value. However, the most applications today are tested only with standard font size and if you change it, even professional applications can have [...]

When Windows are being shutdown or restarted, all runnig applications are closed of course. This can be dangerous, because you can lost your unsaved documents. But there is an easy way to detect, that Windows wants to shutdown and your application can do everything necessary to close properly.