Easy Peasy
Create an alias to the files, and place the alias in the Movies folder
This way, when you start front row, it will display the files (only if you are connected to the network at the time).
If the NAS is switched off, the files will not appear in front row as option.
.....
So my question... what is the easiest way to create an Alias to another location?
I'm a new Apple owner, and I'm just used to right-click dragging a file to another folder and selecting "Paste Shrotcut"