As the others mentioned... use OpenOffice.org. I've used it for a long time and it's a fantastic FREE alternative to MS Office. I'm using the 64-bit version right now and it works smoothly.
I continue to use Office 2003. The student version was fairly inexpensive, as is the still available home/student version of Office 2007. (I know that cheap is not the same as free.)
As the others mentioned... use OpenOffice.org. I've used it for a long time and it's a fantastic FREE alternative to MS Office. I'm using the 64-bit version right now and it works smoothly.