Windows 7 Win7 Networking

[NeoFreak]

I am having problems Setting up Password Protected Folders on a Home network.. Hoping someone here might be able to Answer a Few Q's.

Info:
I have 4 Pc's
Acer Aspire Laptop (win7)/ Custom made XFX game Boxes(Win7) / x2 Old Dell Boxes (XP pro)
All 4 are connected by cat5 to a Linksys 5-port Switch that is connected to a Linksys Router and so on to the internet Box...
I got all 4 computers to share Files By setting up a Workgroup (BC home-group don't work) -Public Network-

Now my problem is that i would like to Password protect share folders, I have tried setting up Permissions.
But not matter what i do the Shared folders Eather work without Password needed or Don't work and gives me an Error.

Can someone offer me more Details on Setting up Private Share folders?

And if possible A way to have Different password for Different Folders?

Possably a Program that i can get to Set up This kinda Sharing?

Thank you if you can Respond...

 

[NeoFreak]

:Update:
Using the Guest account i setup a Account with a password.
Be4 i set up the account i could share the couple of folders on PC1 but with no password after setting up Permissions
and logging onto PC2 i get a box saying:

//(Computername) is not assessable. You might not have Permission to use this network resource. Contact the admin...

Logon Failure the user has not be granted the Required logon type at this computer.

I setup Credentials on these two computers Both using the Guest Account....

Any Ideals as to what i am doing wrong? or not doing?