Why don't you just get the Office 2010 Public Beta version.. Temporary licence code will work until Next October.
http://www.microsoft.com/office/2010/en/download-office-professional-plus/default.aspx
Dump MS Works and remove the PP Viewer if you are installing fully fledged powerpoint from 2010.
well im just going to get the basic home 2010 beta with word,excel dont know if it includes powerpoint , dont know why my new pc came with the viewer if i have not got the full powerpoint program?