Definitely if you have dial up it will be difficult or impossible to get those big PDF files to load. That's a decision that was made in order to keep so many files from being tiny little ones, with hundreds of parts.
The entries from the newspaper index are only that, index entries, and not the actual articles. But you can inter library loan the newspaper microfilms from the state library in Albany to your local library and see what they say. Those are not online yet.
If someone wasn't included in the petition for the will, it might be that she died before the will was proven and left no issue.
And perhaps the Mendon historian, Diane Ham, has some information about the family.
http://www3.libraryweb.org/lh.aspx?id=953, which is a web page that should load quickly.