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1. Go to the K menu/configuration/Mandrake Control Center. Enter your root password, and choose the hardware option. There you will be able to set up your mouse. I am using USB (Logitec MX550) w/ Mandrake 9.1.
2. Dont know
3. Go to K menu/Configuration/Control Center (not MDK ctrl cntr) and choose Look & Feel. There is the option for the screensaver.
4. Also don't know, I got rid of all those icons.
5. Linux runs best on its native filesystems. Journalized, and ReiserFS are the most popular. Search around the forum for more info so you can choose which one suits your needs. Linux can only read NTFS at this time (writing is experimental and will most likely destroy your data), but will read/write to FAT32 if you would like to share a data parition with Windows.