By cursor moving, sometimes it's dirt on the arrow keys that's
causing such an interference. Try blowing it and see the problems
still persist.
As a netbook is quite small, people with larger palms (like
mine) do occasionally brush against the touchpad. So it might be
the case. (or for that matter some tape, or tape residue that's
used to protect the netbook is left on the surface on the
touch pad)
Else, I would reccommend you to send it down to Asus directly.
Most electronic retailers do offer only 7 days 1 for 1 exchange,
Harvey Norman (last checked) should follow the same procedure.
(Unless changed).