I have a quilt top that my great-grandmother made and I want to finish it and not change the way she made it. She hand-pieced it, so some of the blocks are frayed and slipping apart. One friend suggested sewing machine stitching the blocks together, but I think that might put even more stress on the old fabric. Another friend suggested using embroirdery thread and cross-stitching the blocks together.She thought that would keep the fabric from pulling apart and keep the antique look.Do any of you have any ideas on the best way to finish this quilt top so that it can be handed on down?

Couple of ideas to consider - Carefully check the places where it has frayed. If the fabric can be gently tugged together without puckering the fabric around it = consider putting some lightweight fusible interfacing around the area on the back of the quilt. I even put fusible interfacing over the entire back of an old quilt once to give it some structural integrity. You can even use fusible if there are holes that cannot be repaired easily, and you could put an applique or two scattered around the top, covering the hole(s) as necessary. In this case, perhaps transfer a photo or two of your GG to fabric and use that as an applique. you could even applique the entire quilt to another piece of fabric, frays, holes and everything, then use the result of that as the top of your quilt, adding batting and backing as normal.

None traditional method: Quilt it. It will stabilize everything together just the way it is and you can enjoy the art of it for a long time. I've done this many times to preserve the memorabilia. That way there's not a fortune invested in restoration.

I restored an old quilt that I found in a box at a flea mkt. I used light weight fusible web and you cant even see where it was torn then I repaired the hand quilting and it looks like new

I have seen old quilts framed and hung on the wall as a picture. This was done when there are several children to pass things down to. That way everyone has a piece of the quilt. When the top is so fragile, I would be afraid to use in as a quilt.
Sue