Legal Question in Real Estate Law in Oregon

It's impossible to say without knowing the specifics. What did the deed that "put (you) on the title" look like? Did grandpa have any recorded debts or mortgages on the property before he transferred it? Was the conveyance done with the intent of defrauding a creditor or spouse? There's no way for me to guess from here who might have a claim to the property and whether that claim will be successful. My hunch is that you have a specific reason for worrying that someone can take it from you--discussing that issue with your own attorney in private will probably get you a more satisfying answer.