decided to post this how-to because i spent about 10 literal man-hours trying to get this to work. i'll begin in a narrative account...
my windows-based e-machine stopped working about a year ago. would only boot into recovery mode. any other option, including repair, came up fruitless. decided on a fresh intstall of linux to solve my woes. freespire, for one reason or another, was the first distro i came upon. liked it, cept for the default kicker appearance. and also, my logitech marble mouse was functional only as a 2-button mouse. so i tried to edit my xorg file. in tryin to figure out how to get root access, i accidentally deleted the root account. (yea, linux total newbie here)
thru google, i found a tutorial for getting this mouse to work in ubuntu. so i tried that distro next. i dl'ed kubuntu just because kde was the desktop enviroment for freespire. the changes outlined in the ubuntu tutorial for the xorg resulted in a frozen kubuntu splash screen. so then i did more searching, came across someone who got their marble mouse to work in pclinuxos. dl'ed that. at first, after changing my xorg according to the ubuntu tutorial mentioned above (outlined below) pclinuxos froze up just like kubuntu. but pclinuxos wasmore descriptive and told me that the mouse descriptor didnt exist. so below is the xorg changes for ubuntu. and the entry after is what i did to my xorg file.

Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
Option "CorePointer"
Option "Device" "/dev/input/mice"
Option "Protocol" "ExplorerPS/2"
Option "Emulate3Buttons" "true"
Option "Buttons" "9"
Option "EmulateWheel" "1"
Option "EmulateWheelButton" "8"
Option "YAxisMapping" "4 5"
Option "XAxisMapping" "6 7"
EndSection

Section "InputDevice"
Identifier "Mouse1"
Driver "mouse"
Option "Protocol" "ExplorerPS/2"
Option "Device" "/dev/mouse"
Option "Emulate3Buttons" "false"
Option "Buttons" "9"
Option "EmulateWheel" "1"
Option "EmulateWheelButton" "8"
Option "YAxisMapping" "4 5"
EndSection

after editing the former section into my xorg, i found that clicking the small button on the left resulted in what i wanted: holding that button down while scrolling up/down resulted in an up/down scroll on the page i was viewing. but any deviation of the ball to the left or right resulted in a back//forward motion of the page. so i edited the xorg file to the latter entry, and the mouse works as follows: buttons 1/2 are as advertised; your basic left/right buttons. button 9, the small right button, is non-functional. button 8, while held and moving the ball up/down, results in up/down scrolling. no motion of the trackball/buttons results in sidescrolling or back.forward motion. i dont use forward/back nor side-scrolling, so this configuration works perfectly for me. i know this is extremely long-winded and filled with non-sensical phrases, but i wrote this after a long night at the bar and becoming single after 18 months. hope this helps someone ~eric