Re: share problems
1) How are you trying to access the files on them? If you want something that loosely resembles 'network neighbourhood' (or whatever it is called now) you might want to take a peek at LinNeighborhood. Alternatively, you could try Konqueror's implementation smb:// as the url/location. Don't know about Gnome's offering, but I'm sure they offer something similar in Nautilus (or whatever).
2) What is your samba.conf file like? Is the Mandrake machine on the same workgroup? Have you set it up for user or share level? Are the file permissions on the share correct?