In order for CUPS to work with Samba, you have to (at minimum) configure the smb.conf file like this:
[global]
load printers = yes
printing = cups
printcap name = cups
[printers]
comment = All Printers
path = /var/spool/samba
browseable = no
public = yes
guest ok = yes
writable = no
printable = yes
printer admin = root
[print$]
comment = Printer Drivers
path = /etc/samba/drivers
browseable = yes
guest ok = no
read only = yes
write list = root
This configuration assumes a FHS-compliant installation of SAMBA; adjust the [printers] and [print$] share paths accordingly on your system as needed. That is, the directory for your printer drivers can be anywhere on the system; just make sure it is writable by the users specified by the write list directive plus readable and executable by all users. Also, make sure that you have SAMBA passwords defined for each user in the write list using SAMBA's smbpasswd(1) command. Otherwise you will not be able to authenticate.
Also....
When you extracted the driver files, did you create a "drivers" directory in the CUPS data directory (usually /usr/share/cups) and copy the files exactly as named below:
[Windows 2000 and higher]
ps5ui.dll
pscript.hlp
pscript.ntf
pscript5.dll
Finally, did you run the cupsaddsmb command to export the printer drivers?
Best regards,
Steve
P.S. - I bought ESP Print Pro to eliminate all this hassle.
http://www.easysw.com/printpro/