Disappearing cursor!

[runningman]

Hi there, I have small, but also frustrating issue with my X31 2673. Just lately, and in particular when I'm in the middle of something, the cursor vanishes, the screen freezes and things go very quiet! I thought it might be a cooling issue the -base does get quite hot. So I changed the power settings to "CUSTOMISED" and the processor to "FIXED SLOW". I'm not a power user, and I try to conserve energy when I can and I have the minimum of software onboard. I also use Avast! antivirus and Spybot Search and Destroy for spyware so I don't think there's a problem there as they've uncovered no prob's. I realise I can just hold down the ON/OFF button to reboot but surely that can't be good in the long run? Any clues? This happened 3 times while typing message