ms office 2000 problem

we purchase 4 new ibm brand pcs and one hp with xp pro with sp2, if i install the ms office 2000, the word & excel files taking more time to open, each file to open take minimum 1 minute & also for any command (EG: bold, italic,font size,save)all most all comands taking time even i updated core updates wich is available in microsoft, please help to solve this issue.