Sorry to hear that, but that more a case for bad config or bad drivers, or maybe horrible apps like Norton being installed.....or WiFi issues. My missus uses her 2ghz lappy for office 2007 on win7 for all her work...mainly publisher and word...my observations see it running at a seemless speed that wouldnt really benefit much from multicore.
BTW her's is a 2ghz Celeron with Intel onboard VGA, the lowest of the low, she happily watches DVD movie streams and tv shows on it from my network, plays music constantly and not a ounce of lag or jitter....on a wired Ethernet system I rigged in every room of my house.