Reading your post I think you have several issues to deal with. The slow and incomplete loading of gnome I have no idea about at the moment, but let's deal with the business of the desktop not starting up automatically.
You need to edit /etc/rc.conf. I post my rc.conf below. Don't copy it without reading through it and comparing with your own. This file you need to understand and be able to edit yourself. Be aware that it is a Gentoo-specific one, as is the rc-update system. Other distros have other ways of doing what this file does.
# /etc/rc.conf: Global startup script configuration settings
# UNICODE specifies whether you want to have UNICODE support in the console.
# If you set to yes, please make sure to set a UNICODE aware CONSOLEFONT and
# KEYMAP in the /etc/conf.d/consolefont and /etc/conf.d/keymaps config files.
UNICODE="yes"
# Set EDITOR to your preferred editor.
# You may use something other than what is listed here.
EDITOR="/bin/nano"
#EDITOR="/usr/bin/vim"
#EDITOR="/usr/bin/emacs"
# DISPLAYMANAGER has moved to /etc/conf.d/xdm
# XSESSION is a new variable to control what window manager to start
# default with X if run with xdm, startx or xinit. The default behavior
# is to look in /etc/X11/Sessions/ and run the script in matching the
# value that XSESSION is set to. The support scripts are smart enough to
# look in all bin directories if it cant find a match in /etc/X11/Sessions/,
# so setting it to "enlightenment" can also work. This is basically used
# as a way for the system admin to configure a default system wide WM,
# allthough it will work if the user export XSESSION in his .bash_profile, etc.
#
# NOTE: 1) this behaviour is overridden when a ~/.xinitrc exists, and startx
# is called.
# 2) even if ~/.xsession exists, if XSESSION can be resolved, it will
# be executed rather than ~/.xsession, else KDM breaks ...
#
# Defaults depending on what you install currently include:
#
# Gnome - will start gnome-session
# kde-<version> - will start startkde (look in /etc/X11/Sessions/)
# Xsession - will start a terminal and a few other nice apps
XSESSION="Gnome"
A few general points. Make sure you have all the documentation and have read it. Look for the handbook and the documentation listings page on the Gentoo website. The Gentoo wiki is useful but not official and is of variable quality. Gentoo is a do-it-yourself distro and demands much, much, much more from the user than Ubuntu. I notice you call yourself a Linux 'nub'. I mean this kindly but you may find Gentoo too much just yet. I didn't manage to make a successful Gentoo install Until I had been using Linux for over a year and even then it was a helluva steep learning curve. I don't want to put you off but I warn you - many pitfalls lie ahead. :wink:
How did you install Gentoo? From the Gentoo CD? From a stage 3 tarball using another distro? Somehow else? The default Gentoo CD install only gives you a cut-down version of gnome. Try 'emerge -pv gnome' from a root terminal and you'll see what I mean. I don't think this is the cause of gnome not running properly but it's worth bearing in mind.
Edit; Whoops! Almost left you in the lurch. As well as rc.conf, check /etc/conf.d/xdm. It's self-explanatory. Here's mine:
# Tell X to always start on VT7. Otherwise it autodetects the first available
# VT, which means it has to wait until all gettys are started so it doesn't suck
# up a VT that should have had a login prompt (very slow).
# If XSTATICVT is on, the login manager will start as soon as possible during
# the boot process. If you want X to dynamically start on the first unoccupied
# VT after all gettys have started and you are using xdm, also remove the "vt7"
# from /etc/X11/xdm/Xservers.
XSTATICVT="yes"
# What display manager do you use ? [ xdm | gdm | kdm | entrance ]
# NOTE: If this is set in /etc/rc.conf, that setting will override this one.
DISPLAYMANAGER="gdm"
Edit 2: That's 2 dashes before search in emerge --search. Something wrong with the board's font - in my machine at least. :(