Tried the Safe Mode thingy,
Saab, but no improvement there, and I'm sorry to say that I didn't really understand the rest of your post.
(Techno-retard, me.)
Definitely not the mouse,
Henry ... that works perfectly on another computer and that wouldn't really explain why the lappie's own touchpad prooooduces the ssssssssssameeeee effect. Also, any other mmmmmmmmmmouse attached to this computer does the same thing.
One shall have to get this computer repaired if one wishes to continue uusing it.