How secure is Samba

I ran across a link on the web panel that leads to a page showing how to use Samba instead of FTP to manipulate files.

It sure sounds tempting. You can drag and drop.

But how secure is Samba, compared to FTP?

(And as a side note, the instructions on that page have us using the lmhosts file. I use Samba between my Win98 and Linux boxes here at home, and I use hosts instead of lmhosts to define IPs. Can anyone give me a URL that explains the difference between those two files, and when you use one, when you use the other?)