Mouse & KDE

I have a Razer Boomslang 2000 hooked up to my USB port.  When choosing
the mouse in KDE, what would I put?  I've been using 2 (MouseSystems)
but, it doesn't work.  I tried 3 (Bus) and it doesn't work.  Which would
it be?  Also, when installing gentoo, does the it put the mouse as
/dev/mouse?  Or where?  I don't remember doing anything like that during
the install, so does it do it automatically?  

While in /usr/X11R6/bin/xf86config, I will choose for my horizontal
sync, the 9th option.  My monitors user manual says "1280x1024 @ 75 Hz
(VESA)" so, I choose 9 since it's closest (9 says 74 Hz, 10 says 76 Hz).
But, when I startx, I only see the top left portion of the screen,
unless I put it down to 640x480, then I can see it all.  In case you
need to know, I have a ViewSonic A90f+ 19" moniter and a GeForce 2 GTS
Pro video card.  Thanks a lot for your help.

Glenn