Q: Have lost control of the track pad

Hi, the track pad on my mid 2010 macbook pro has suddenly developed a mind of its own. The cursor is moving randomly by itself and clicking on files and applications making them open and close and constantly right clicking and highlighting everything. I can only get control if I connect an external mouse and shut the track pad off.

I have turned the computer off and on, repaired disc permissions and reset the system management controller and nothing has fixed the problem. The issue has become less severe as in I can move the cursor now using the track pad but it doesn't always go where I tell it but it is still constantly right clicking, highlighting everything, clicking and opening/closing programs when I didnt tell it to and even closing/opening programs if the cursor just moves over an icon without clicking.

I can't currently run a diagnostics trial because I don't have the required software disc at the moment - it is being posted to me

Does anyone have any ideas on how to fix this or is this an I need to buy a new computer situation? Thanks for any help

OS X 10.6.8

2.4Ghz Intel Core 2 Duo

4GB Memory

250Gb HDD