[CentOS] CentOS/RH 5 Samba as PDC+NIS w/o LDAP?

For those who are new or forget - I have a RHEL 5 Server and a few 
dualboot XP w/SP2 and CentOS 5 systems.  The Linux machines were installed 
straight of CD/DVD, no patches.

I was initially going to try a single sign-on to the RH 5 box via LDAP, 
but RH says it simply isn't possible and I don't know my way around LDAP 
other than it is a database and exists.

So, option 2 is to simply have the RH 5 Server act as a Windows PDC via 
Samba and use NIS to enable users to log in, all the while, in either 
situation, having the RH 5 box serve out the user's central home directory 
- mounted as a drive letter under Windows, or exported under Linux.

I've spent much of last week and much of today [trying to learn] LDAP, and 
today, finally deciding to dump that, but proceeding with Samba as a PDC.

For Samba as a PDC - what is the best way to have Win XP Pro w/SP2 
successfully authenticate to Samba as a domain controller with encyrpted 
passwords?  And, to have Samba establish the user's home directory as a 
mapped drive?  I've used a barrage of web sites showing various smb.conf 
confing files but can't yet get my test XP machine to authenticate to the 
domain I set in my smb.conf file.

For NIS - what is the best way to permit the user to log into their 
account, created on RH 5 server, and have their home directory exported to 
their workstation?

I presume there will be no problem with users simultaneously logging into 
multiple workstations, be it Linux or Windows?

I only bother the list because I have scoured so many web sites, some with 
a variety of options, I believe I'll get the best answer here.

Thanks.

Scott