Here is the question (or should I call it a cry of desperation?):
"I hope beyond hope you can help me. Grandfather died in 1988. Grandmother was co-owner of the house. Aunt was named executrix of Grandfather's will. Aunt lost the original will. We have copies. The will wasn't probated. Grandmother died in 2001. Her estate was probated and dealt with, except for house (paid off) which we cannot sell due to joint ownership. Not one lawyer will touch this. Not sure where to start. HELP!"
This isn't really that complicated. If no lawyer will touch it, it's because you're asking the wrong lawyers. Find someone who specializes in wills and estates by calling the Canadian Bar Association (not the Law Society) in your province. You can also google wills and estates lawyers, then read the profiles of lawyers in your area to determine whether they have the necessary experience.
In order to proceed with the sale of the house, first your grandfather's name must come off the title. To do that, your aunt needs to probate your grandfather's will so that his executor will have the legal ability to sign documents on his behalf. If the original has been lost, she needs to try to probate a copy of it. That isn't done often, but can be done in certain circumstances with the permission of the court. It's more complicated than probating an original, but not impossible.
If your aunt is reluctant to act, you might remind her that she may be personally responsible (i.e. not covered by the estate but out of her own pocket) for any loss that occurs to the house, loss of rent since 2001, any capital gains tax that accrues while the house is waiting to be sold, and any court costs/lawyer's fees if you have to force her to take steps. Perhaps she would find that information to be motivational.
It wouldn't have been necessary for your grandfather's will to be probated if your grandmother had taken your grandfather's name off the title herself after he died. She, like any surviving joint tenant, could have simply gone to the land titles office with a death certificate and had the title changed over to her name alone. But since she didn't, and may have had no idea that she could even do that, now probate is needed so that someone has legal authority to deal with the title.
Once your aunt obtains probate, she will have the legal authority to take your grandfather's name off the title. After that, the executor of your grandmother's estate can arrange to sell the property. The proceeds will go into the grandmother's estate, not the grandfather's estate.
This situation isn't really all that unusual, in the sense that surviving joint tenants often don't realize that they have to do anything with the title to their home. They understand that when one joint tenant dies, the other automatically owns the house. The word "automatically" is misleading, as it implies that no action needs to be taken. More accurately, the surviving joint tenant has the right of ownership, but must make sure that the title record is brought up to date at the land titles office.
In your case, the loss of the original will does complicate things somewhat, but it's not impossible to deal with. The key for you is going to be finding someone with the required depth of knowledge in this area of law.