Shares configuration?

Hi folks,

I was wondering if you can help me to set up the shares for a small 3
PC network where two PC can see and access each other shared folders,
but one PC can _only_ be accessed by the other two but _not_ access
them?

In other words:

I have PCs
A, B, C

I want PC A to be accessed by B and C but not be able to access them.

(mmmm is that clearish?)

As an additional bonus, I'd like for all PCs to be able to print on
all printers connected to any of them (i.e. PC "A" can print on the
local printer of PC "B" but not be able to access any of the folders
in "B")

Let me explain the reasoning:

PC "A" is used by the kids. PCs "B" and "C" are my work PCs. I do not
want any chance that the kids can rummage through them and cause havoc
(by mistake), but I still would like for them to print using my laser
and colour printer when necessary.

Operating systems:

There is some flexibility here, as I have licenses for 3 XP home, 1 XP
professional and 1 Windows 2000

at the moment "A" (the kids) is running W2000, while "B" and "C" are
running XP Home, and obviously, I'd be happier if I did not have to
reinstall any OS.

Thanks a lot for all the advice

Lorenz