Oral Contracts in the state of Massachusetts

My mother reached an oral agreement with her brother in law and his wife in 1984. The oral agreement was a five year agreement, that is, she orally agreed to allow them to purchase the property they rented within the next five years with certain conditions. They wish to enforce the agreement 17 years later. What is the normal expiry on oral contracts in Massachusetts and is that length of time the same now as in 1984? And does it matter as the oral agreement was essentially a five year option?

With few exceptions, oral contracts for the sale of land are not valid; neither are contracts that will take over one year to perform; therefore, the contract is not valid. However, even if one of the exceptions applies (for example if they paid the taxes and mortgage and made improvements on the property), as you said, the contract was a 5-year option and the 5 years is up; therefore, they have no rights left under the agreement, even if it was valid.