Sharing issues

Hi,

I want to be able to share a folder with different
security levels. I only have 2 options...I can either
share with all users able to change files, or other users
can only view files. Now, I went to help on this and it
said that I should be able to set permissions and number
of users to connect and so forth, but I do not have those
options. Plus, there are 4 tabs at the top of the
dialogue box in the help section, but when I actually
right click and pick sharing and security, I only have 3
tabs. Is there a setting somewhere? This is with XP
Professional on a small business network (about 20 comps)
and we are all networked together and see the internet
through a hub!

I hope I made this clear enough!

Thanks!

Jim