Ask your friend to close all "Running programs", I think that ME. is the same as 98, if so, then use Ctrl/alt/del keys together to bring up a window displaying all programs. Close each one down, one at a time, except for "Explorer", and "Sys. tray", then try defrag again, should work ok.
If not, then re-boot and tap the F8 key, this will start up in DOS mode, you will see 4 options, choose "Safe mode" then after it has finished loading the basic drivers, try defrag again. j.