If she is not executor, she can't sell anything that was her late husband's property.
She is entitled to be told what the will provides insofar as it concerns her. It is difficult to see how they can avoid telling her the gross value of the estate, because it is a material fact in her ascertaining if she is getting her statutory entitlement. The executors do not have to tell her about individual bequests at this stage.
When probate has been granted, the will becomes a public document, and she can inspect it.
If the executors are playing silly games, and not co-operating with her when she has a legal right, it sounds like time for her to engage a solicitor to defend her interest.