Creating User Accounts with or without Active Directory

[J'son]

Guys,

I need to build a web intranet application that can automatically
create a user account when a new user registers on the site. The user
account will be on the web server, member of the guests group (or some
other limited group), and get read permissions to a special folder.

I've tried playing with Active Directory on my local box, but I'm
running Win XP Pro, not Win Server 2003 so I don't think its available.
My production server will probably have access to it however.

So my questions are:

Can I use Active Directory for this sort of thing? I'm looking for a
code example for creating a user account, assigning permissions, et.

If I can't, what was the old ASP, VB 6 way of doing this? I'm sure
theres an older interface out there somewhere.

Thanx!

J'son