"Wake on LAN" my Mac Mini from my PC?
You normally have to access a shared resource on the Mac rather than use a magic packet.
The simplest way is to set up file sharing (allowing SMB for the PC) and try to access that from the PC.  This could be any folder you like so you do not have to worry about it being visible to others on the network and can (should) be password protected.
Other things that should work are:

Shared printers / scanners
Music
Music play lists
Screen sharing (I think but that may have been via VNC on the Mac)