Heylo everybody, i'm sure this isn't a huge problem to sort out but really annoying me

I've just seriously started to learn about and use Linux on a spare machine and am running into Samba problems under Debian.
I have a very simple 4-PC Windows98SE network with Network Neighbourhood shared drives.
These pcs have static IP's, with "share-level access control" set in "Network Properties".
***I have set up Samba Linux box and wish to make shared drives accessible from the Windows machines, with user name/password access.***
The problem is that whereas the Linux box is visible in Network Neighbourhood, it is not accessible.
A dialogue box asks for a network password to \\Tommy\IPC$, but does not allow the input of a user name.
Here is a copy of my smb.conf file:
[global]
workgroup = toms
server string = Debian Box
; load printers = yes
; printcap name = /etc/printcap
; printing = cups
guest account = nobody
invalid users = root
user = tom jon (user accounts on machine)
log file = /var/log/samba/log.%m
max log size = 1000
syslog = 0
security = user
encrypt passwords = true
socket options = TCP_NODELAY
dnsproxy = no
unix password sync = true
passwd program = /usr/bin/passwd %u
passwd chat = *Enter\snew\sUNIX\spassword:* %n\n *Retype\snew\sUNIX\spassword:* %n\n
[homes]
comment = Home Directories
browseable = no
; [printers]
; comment = All Printers
; browseable = no
; path = /tmp
; printable = yes
; public = no
; writable = no
; create mode = 0700
[hdc1]
comment = Hdc1
writable = yes
locking = no
path = /windows
#automount
preexec = /bin/mount /windows
postexec = /bin/umount /windows
[zip]
comment = Zip
writable = yes
locking = no
path = /zip
#automount
preexec = /bin/mount /zip
postexec = /bin/umount /zip
[cdrom]
comment = CD-ROM
writable = no
locking = no
path = /cdrom
#automount
preexec = /bin/mount /cdrom
postexec = /bin/umount /cdrom
As you can see, I have tried to solve the problem of the Windows boxes not allowing user name input by putting in the "user=" option.
I have also chmodded all the listed shares correctly far as i know

I have not tweaked the Win98 Registry at all.
If anyone can help me configure Samba or tweak the Windows machines, or see problems in the config above. please help!! It's probably really obvious to anyone more experienced, but i have read loads of samba docs and they confuse me beyond belief

I don't want anything fancy, just simple password-protected file shares.
Thankyou in advance,
Tom.