For me Arch is very easy to install. I would recommend downloading a recent snapshot of the netinstall or core iso from here: http://releng.archlinux.org/isos/
and read the Beginner's Guide (https://wiki.archlinux.org/index.php/Beginners%27_Guide
) as well as the Official Installation Guide (https://wiki.archlinux.org/index.php/Official_Installation_Guide
) thoroughly before installing it. I would recommend just going with the default source of core-local instead of core-remote as the you'll be able to actually install and configure the system.
After rebooting, creating a normal user (if need be), getting the wired or wireless interface up and running and connected to the network using
and uncomment the mirrors you want to use. After that run
to get the latest databases from the repositories, making sure that you press n after the question asking whether you want to update pacman. Next thing you do is run
pacman -S gcc gcc-lib
and press n at the same question. The reason for this is that there is an odd circular dependency. After that you can finally run
pacman -S pacman
to update pacman and then
to update the entire installation. Only after doing all that should you install anything extra with pacman and configure the system.
After that, it's just a matter of building on the base Arch gives you to get what you want. There is no GUI, automatic storage mounting, automatic network configuration or much automation at all by default. It's just you and the command line for a while.
As for the support for the older ATI graphics (I owned a Radeon 7000 64MB (AGP)), you're in luck. There is the open source driver which will support it. Check here for a listing of what the driver currently supports (everything under R100 applies to the 7000): http://www.x.org/wiki/RadeonFeature
The wiki is a excellent source of information as is the Arch BBS (Forums). You can also check them on irc.freenode.net at #archlinux if you have a registered nick.
Hope it helps. Post here should you need any help. There are a few other Archers like myself around.
Eureka: X200s (7470-5HU), Arch Linux
Mirandra: T22 (Unknown), Arch Linux