Confusion around Device Driver Install/un-install

[vbportal]

Hi,
Could someone please clear my confusion about what
constitutes a device driver install and uninstall.

For a graphics card device driver, I take either the CD
which comes with the graphics card and allow it to auto load
the device driver
OR download a new device driver from web and double click to
let it install itself (I tried to use the device mgr to install but
I believe it looks for a specific file type and not a self
extracting .exe file).

When I want to uninstall the graphics driver, I need to
go to "add/remove programs" to remove software which
the above methods of installation have added (I guess
the device driver consists of a UI component and the driver ?)
and I guess I need to go to the device mgr to remove the driver.

So, I'm confused / not clear which way things should be
done to ensure that I install everything and then
uninstall everything AND I see a number of ways
someone can access XP for driver installation/uninstallation
and am not sure how they are (if they are) interrelated:
(1)start->control panel->add/remove progs
(2)add hardware (not clear in which cases this is used (non-plug and play)
(3)add/remove programs
(4)"double clicking" on a device driver file downloaded from web,
(5)control panel->system->hardware->advanced->device mgr
(6)auto install from CD

Thanks,
Vjeko