please help me get my mouse back!

[robbo13]

hi, im totally new to all this. I installed 10.4.11 on my dell d420 and on of the issues was that it didnt recognise the trackpad, only giving me basic mouse options so no scrolling etc. So i installed this: http://forum.insanelymac.com/index.php?showtopic=47272

 

and that pretty much stopped it working at all. I then tried to remove this by doing what it mentions in that post

sudo -s
rm -rf /System/Library/Extensions/ApplePS2Controller.kext/Contents/PlugIns/ApplePS2Trackpad.kext

 

and

rm -rf /Library/PreferenPanes/FFScrollPreferencePane.prefPane
rm -rf /Library/Preferences/com.apple.driver.ApplePS2Trackpad.plist
rm -rf /Library/StartupItems/FFScroll
rm -rf /usr/local/bin/FFScrollDaemon

 

before i installed it i took a copy of my original ApplePS2Controller.kext in case i needed to restore it. So how do i restore it as i cant just drag and drop it from the copied location into /system/library/extensions.

 

At the moment when i start up i my trackpad does nothing at all, please help!