Yes, you can do that.
Just add them to Samba (smbpasswd -a (blahuser)), then create a folder for them on the server (in the example, //home/blahuser). When they pass their credentials, you can have Samba direct them to a folder no problem.
Something like this will direct a user to a directory under the /home share with their username, then make them the owner of the file and no one else will be able to open it.
Code:
[Users]
comment = User files
path = /home/%U
public = no
read only = no
writable = yes
browseable = yes
create mode = 0700
force create mode = 0700
directory mask = 0700
force group = users
That's a modification of what I use on my Samba server at home. No matter if a user browses to that share or if they type it into the run box (ie, \\servername\users), it will redirect them to /home/username. That's how I keep my wife out of my home directory and vice versa.
Also, security = share is a pain in the arse.