Why does my "DEL" key act as an "Arrows direction " Key?

[Mel Holt]

toshiba Qosmio G45-AV680, my delete key sends the cursor off on it's own and
it won't stop. My DEL key acts as though it's an "ARROW's" key. Sometimes it
does the job (Deleting) but most of the time it sends the cursor on it's way
without stopping? How I fix it ?

 

[grammatim]

Unscrew the keyboard and clean underneath? What does this have to do
with Word?