I will try that utility out.
Basically what happens is quite frequently and predictably--like some timed process is trying something--the system will almost completely lockup. The mouse will become very flashy and only every second or so do an update draw on where it is, but the computer will otehrwise be pretty locked up for about 10 seconds. If music is playing it will loop the same bit over and over. Also, copying data from that HD to an external or even to itself I cannot do it and get tons of errors. Checkdisk seems ok and I did defrag (it was severely defragged before doing that). I unplugged the DVD player to see if it was messing up something, per comments elsewhere on the web, but it wasn't.
It is a maxtor, yes

I will run that util and check for results.