Can't open .xls files in Works, but Open Office will open .xls files. I haven't played with the spreadsheet to be sure everything works, and I'm not 100% on the compatability, but it does open, and the graphs show up. The 6th sheet looks a bit weird, and some of the graphs aren't titled, but I could probably fool with it enough to make it work properly.

OpenOffice is good stuff. I'm just too lazy to go find a good Office XP dl.