How to backup a game DVD on hard disk in ISO format?

Solution 1:

gnu ddrescue is designed to work in such situations - its a dd style tool designed specifically for data recovery. You'll need to boot into linux (maybe with a liveusb to use it).

Howtogeek suggests running two passes - the first is
ddrescue -n -b 2048 /dev/cdrom <ISO file> <log file> which backs up the easy to recove parts of the disk, and a second ddrescue -d -b 2048 /dev/cdrom <ISO file> <log file> which adds harder to recover blocks

Solution 2:

install cygwin from here and install mksiofs into cygwin(however if i remember it installed by default), Then use mkisofs from command line.