> Just trying to find out whether scanning using the adf works over a network to a pc ?
Yes but you need to pull the scan job from the PC as opposed to pushing the job from the control panel of the printer unless you previously installed the printer as a network printer and the approrpriate HP Scanning software is available for your OS.
> Can you scan from the printer to the pc or only from the pc itself ?
PC to printer is pull scanning. This should work with many 3rd party scanning applications such as MS Paint and MS Scan and Fax wizard. Printer to PC is push scanning. Push scanning requires an HP scanning client to be installed on the target PC otherwise there is nothing there to recieve the scan job.
The other work around would be scan to Email if your printer happens to have either internet access or you are on a network with an email server locally available to your LAN.
> Scanning using the adf does it scan all the pages into 1 document or does it scan and save each page into separate documents ?
This will depend on the document type that you want to publish your scanned job as. For example smart image formats such as .TIFF and .PDF can manage multiple pages in a single job. Dumb image formats such as .PNG, .JPG or .BMP cannot handle more than one page per document.