Thanks for such a quick reply.
I don't have a homegroup though. The Network and Sharing Center doesn't appear to have that option for me :S
I believe this is through Windows Media Player sharing.
Edit - It appears I have turned this off somehow...
I made a Homegroup... then I turned off the Homegroup... and I selected no for each type of media to share with Homegroup...
And I have all advanced sharing settings to off now...
That appears to have fixed it???
This is one thing Windows always does poorly... aside from very epicly disgusting management of hard disks.
Thanks for the help though