Samba : public / user acces and password questions

Hello !

I have two questions :
1) I can have a public share when I have the option security = share
and a user share when I have the option security = user, but then, the
public share doens't work anymore. Is it possible to have public shares and
user share activated at the same time ?

2) Say my aministrator account name on WinXP is toto. This account on WinXP
has no password. Is it possible to get access to user toto share on Samba
server with no password defined on WinXP ? (doesn't seem...)

Thanks for any answer !