>Again, if I was in charge I would have put VFP on a cheap single proc box running Win2000 or Win XP Pro.
Tell them again, including perf data from your home machine. If adequate, this is possibly cheaper than to pay your hours. If they decline, check the opening times of files between both machines.
Check the percentage of free space on the server, and how much the disks are fragmented.

Hint: for such tasks it usually pays off to use different disks with input and output files if you have control.

HTH

thomas