I have a 40 GIG Western Digital.  I use my computer primarily for gaming and
internet surfing ect.  Do I pay the $$ for Perfectdisk or go with one of the
free ones like IObit Smart Defrag?  I am not sure why those are free, I do
not want a malware.

every time i start my pc, i get an error message.  i can't tell if its
affecting my pc but its annoying can anybody tell me how to fix this problem.
RUNDLL
Error Loading ams491.dat