[CentOS] Minimal Install?

Hello list,

I'm testing CentOS 5.2 as a possible Xen Server (i.e.: dom0) but the
default no-items-selected still installs cups, portmap, and many other
thing I don't want in a dom0 installation.

I've already removed the packages I don't want, and replaced sendmail
with postfix (I need a mailserver because of mdadm/smartd) but
there're some executables I don't know what they do (gam_server for
example)

Two questions:

1) Is there a _real_ minimal install?

2) Is it possible, using yum, to know which packages holds what file?
(like dpkg -S in Debian/Ubuntu)


Many thanks in advance,
Norberto