Just Keep in mind cleaning thoroughly is the first step. You will, and I repeat, come across defective DVD's that are brand new that you will never in this lifetime copy.
But you say it plays fine in my PC and stand alone player, true they will, but no matter what program you use you'll never get it copied. I'm not saying this is the case with this particular movie since there have been issues with it, but somewhere down the line you'll run into one or more that just can't be copied because of errors that only manifest themselves when trying to copy the file, been there, done that.
You can read about the Grudge issues here, looks to me by using the latest versions of CloneDVD and AnyDVD corrected the problem, don't know, never tried, not fond of horror flicks.