About 6 months ago my computer started locking up while working on a Word
document. Even a simple 1-page document with no graphics. Doesn't happen
right away, maybe 15-30 minutes into working. Screen and mouse freeze, then
screen goes black. Computer does not turn off so I turn the power supply off
and start over. Any ideas on how to stop this annoyance??? Many thanks if
you do!!!

Gateway 700 computer - 5 yrs old
Windows XP w/SP2
MS Office XP Small Business 2002