my son was playing on addictivegames when the puter shutdown and rebooted and then began to behave in the same manner. booting to normal mode caused a blue screen then reboot, booting in safe mode with command prompt, halted at sptd.sys then rebooted. last known good does not work.
luckily i have a dual boot system and booted into linux to rename the sptd.sys file located at "C:\WINDOWS\systems32\drivers\sptd.sys"
i rebooted and selected to boot Windows normally at i am know typing this in Windows just fine.
not sure what is going on with that file and if addictivegames had anything to do with it in anyway. currently running virus scan (thats the other thing the anti-virus was temporarily disabled).
you can google "linux liveusb" "linux livecd" or see http://www.pendrivelinux.com/crunchbang-linux-flash-drive-install-via-cd/
and google "how to mount ntfs partitions under linux"
you can rename a file by typing "mv sptd.sys _sptd_._sys"
you do this in a terminal window within the Crunchbang liveusb/cd you would use the "Windows Key) + "t" combo ~ Crunchbang calls the Windows key the Superkey.
best of luck.