If you have a Rage Mobility video, maybe you should think about upgrading-it to 16mb, then you will have the benefit of an 128bit memory bus instead of the 64bit memory bus when only 8mB is installed.
Ok, format your c: drive. :)
Irfanview is not an installed program as such. When you want to install-it, you create a directory of your choice and unzip the irview.zip file to it, then you could go in Options/Properties (a menu in IrfanView) and select the file associations you want to...
If your sound card is not automatically detected, press <Ctrl> <Alt> <Backspace> to exit KDE OR GNOME (or wathever), and type sndconfig and let this program detect/configure the soundcard for you. Type startx to go back in kde or gnome or etc.