Matt,
I'm not Scott either but you leave so much information out.
Does your MIL need income now? She has just over $3,200 coming in per month. Is that enough to cover her current expenses?
How is her health? People that suspect they won't live "forever" or at least a very long time probably shouldn't consider any type of annuity. Buying it through Edward Jones pretty much guarantees a poorer financial product than Vanguard. The prior post showed a much better return through Vanguard but there are all sorts of details that may be distorting this. I'm almost always against annuities because of their poor financial performance.
Does she have any other assets? Her biggest financial concern is probably long term care. What are her plans for that? Realistically, she should have a combination of fixed and equities. Between her pension and SS, she has a pretty high "annuity" level.
Can she physically live in her home for the the next 5 years without assistance? If not, it's probably time to sell and pocket the equity. If she can, the $60K mortgage is probably a good thing to pay off since I suspect she doesn't itemize.
Good luck. My wife and I are dealing with my FIL's finances. It's a thankless pain in the rear.
Ken