Install as Server vs. Custom

Using Red Hat 6.2 cd.
P75 w/ 16MB Ram
2-ide hard drives each about 1.5G

I'm curious about the install choices, Server vs. Customized.

I would like to install as server because I'm first experimenting with
server software and I didn't want to exclude anything causing dependency
issues. Also, I want the default partitioning as Server. No reasons other
than trust and curiosity and maybe I'm lazy.

Doesn't the Server installation install the X windowing system by default?

Can-o-worms:
When trying to install X windowing by using the upgrade option it appeared
to me that one could install or reinstall packages or groups of packages
through this approach. I've never heard anyone suggest this so I imagine
there's some real problems doing that.