Both Gnome and KDE allow you to mount Windows shares (on Gnome, menu Places->Connect to Server). From a command line, you can list resources on a server with:
smbclient -L \\server2005
You can mount a share with mount (filesystem type cifs or smbfs).
Microsoft Access
runs on WINE, so you should be OK there.
WoW also
runs on WINE, though you might want to get
Cedega to make your life easier if you are going to be gaming on Linux.