Posted 11 September 2008 - 10:23 AM
If you're running Windows XP Home Edition, this is done easily enough provided your drive is formatted under NTFS. Open My Computer right click on your C: drive, go to properties, and look under File System to see what your drive has been formatted as. If you put a password on your account, by default your My Documents folder will not be accessible to other users. For this to be effective of course, you must be the only person using your account, no one else should know your password, and you should log out or lock your screen [Windows key + L] to prevent others from accessing your account. If you have Windows XP Professional it's easier to set NTFS permissions for individual folders and grant or deny access to anyone based on users or groups, although that's a more advanced task.
To encrypt a flash drive you'll need 3rd party encryption software of some kind, I haven't worked with that sort of thing so I'll let someone else field that.