Because a PC monitor does not show a static image - it is being re-drawn every 1/60th or 1/75th of a second (whatever the frequency of the monitor display is).
When you look at one in real-life, the image looks stable because your eye retains an image for 1/24th of a second, so sees a complete...
The file: directive is fine, but you need to find the 'real' name of the drive. As you say, different people can use different letters to map a network drive, so you must specify the real name.
Go to a command prompt and find the remote name the drive maps to (it is one of the 'net' commands -...
What do you mean by 'link'? Do you mean you want to hyperlink back to the first page?
A link for "../otherwebpage.html" would work in pages one level below it.