kernel.org's kernel: building and root file system

Hi;
      I am new to this and I have some questions of "what's next?" after
having downloaded the latest kernel from kernel.org:

(1)   Since I am going to build the kernel for PPC platform and
architecture, running `make xconfig` won't bring up the right set of
configurations for your target but the default which is a generic X86
architecture and platform. What is the usual step so that I will have the
configuration set for my target? I think of 2:

      (i) copy arch/ppc/configs/<foo>_defconfig to $SRC_BASE/.config; `make
xconfig`
      (ii) `make xconfig`; and inside the X-window, open the
arch/ppc/configs/<foo>_defconfig and save it for your architecture.

      I tried (ii) but after having opened the <foo>_defconfig, it is not
reflected at all in the X-window. It is still showing the default
configurations.

(2)   Ok, you have the kernel running on your PPC target. How about the
root file system? Where and how can I have/build a generic root file system
that works with kernels running from kernel.org?

(3)   Toolchain. What cross-toolchain is generally used to build the kernel
for your target? For PPC, I come across this
http://penguinppc.org/dev/crosstool.php... Is that popularly used to build
kernel from kernel.org for PPC architecture and platform?

      Thanks for any comment and insight.

Regards,
TEH