Hi and welcome to the forum,
I think it is anybodies guess as to what you have done to the system as there really aren't enough details to go on!.
On a notebook/Netbook, the touchpad mouse is normally switched /on/off by using the FN (coloured blue on your keybord) and maysbe the F5 or F6 key, this of course varies from model to model!!.
Another option is to borrow; beg or steal (only joking!) a USB mouse from someone/somewhere until you find what is causing the problem!.
Try running "DPKG" (Network cable is necessary!) in recovery mode per this guide:
viewtopic.php?f=5&t=2247Apart from that; all I can really suggest is to try another install and follow this guide but
DO FORMAT THE HOME PARTITION assuming you haven't already copied data to it!.
viewtopic.php?f=6&t=4848If and when you manage to boot successfully, check out the
System Settings > Hardware > Mouse & Touchpad settings!.
Let us know what happens!.
Regards Wolfman