Something like this:

/dev/sda1 /dp1 ext3 defaults 0 0

in your /etcfstab file should do it. That entry is for an external USB
drive mounted on the /dp1 partition, it might be /dev/hdb1 for an
internal drive, but if you've been manually mounting the drives, you
probably know what the device name is.

> 3)is there a way to get Samba to start automatically when the
> computer is rebooted?

Do you have an entry like this in your /etc/rc2.d directory?

abc@zaphod$ ls -l *samba*
lrwxrwxrwx 1 root root 15 2008-03-15 00:13 S20samba -> ../init.d/samba

When I installed Samba with synaptic, it created the init file and
link from the rc2.d directory, I didn't have to do anything other than
edit /etc/samba/smb.conf file and restart Samba.