A tip for samba: make sure that all the firewalls, both the one in Mepis and the ones on the systems you are trying to see, are down. In guarddog you can simply disable it by ticking the checkbox (you'll find it).
After it is found, find out which IP number your Mepis system is, and then add that to the firewall config on the Windows machines. Then you can also add the Windows systems to your Mepis firewall and that's it (I use Firestarter so I don't know how to do this in Guarddog).
Sounds simple, but that silly bit took me three months *laughs* I figured I'd save you that at least
Oh.. and go through the Control Center for the sounds bit, you can configure it in there.