Weird after installing slackware,i've chosen to install the boot in master boot record and windows boots normaly,i mean lilo doesn't show up.

Change BIOS to boot the harddrive you installed slackware on

Why do i have worse framerates in Quake 4 in linux comparing to windows?

I'm told that more time is spent optimising the windows version because it has a larger potential audience. It plays OK on my box under Linux - is there a way to tell what frame rate it is using?

36/46 Fps.800*600 medium quality.

Hi, hope not to be too offtopic here, but i must say i have better fps on linux quake4 than in xp, remember to tweak your kde (or any other window manager) to the highest refresh rate your video card, and most important, your monitor officially supports (be carefull here, going higher may mean permanent damage).
Mine is 75Hz for a viewsonic 900 lcd. (Right click desktop, configure desktop, display, size and orient..Refresh rate)
I also like to play with no window manager, saving resources, so i boot to non graphical mode, instead of startx or startkde i type xinit or if you are using kdm pick failsafe session. That's it, start your game without unused resources. Happy fragin