My mother is joining us this trip, she’s 65 years old with average health. I wanted to ask if the following rides would be ok for her:
Barnstormer
Soarin
Flight of Passage
Seven Dwarfs Mine Train
I’ll be riding these, wondering if anyone has experience with that age group on these:
Splash Mountain
Expedition Everest
Tower of Terror
Thanks in advance!
I think it probably depends on your mom.
My parents are in their early to mid 60’s - my Dad would be fine on Barnstormer, Soarin’ and probably 7DMT. (Can’t speak for Flight of Passage). My mom wouldn’t do any of them.
My Dad would probably also do Splash Mountain (he did on the last trip 4.5 years ago) but I doubt he’d do EE and TOT - he has heart trouble, though and isn’t a big roller coaster fan.
She will love Soarin’. Nothing uncomfortable there, just a wonderful ride.
Barnstormer and Seven Dwarfs are undoubtedly rollercoasters, but very mild ones. If she wants to try them, she really should. I would prioritize Seven Dwarfs, since it is so much more than a coaster (you get to see different parts of the Snow White story along the way - very cool).
I haven’t been on Flight of passage yet.
Splash mountain will be fine for her if she doesn’t mind that last hill. It is really less steep than it looks from the outside. The “story” on that ride is so great, it is definately my favorite ride in MK, if she is into Disney theming it is worth a try. I would suggest she wears a poncho, though 
Unless she really likes rougher roller coasters, I would skip Everest. The same goes for Tower, both rides are somewhat rough to your body, especially the back.
As a former rollercoaster operator I can tell you that it’s definitely health and temperament more than actual age. I strapped in some people who looked older than dirt and they all came back in good health! We had one guy who was 77 and would ride my coaster (a big, fast one) over and over if there was no line.
Just be aware that any of the more thrilling rides come with the following restriction:
WARNING! For safety, you should be in good health and free from high blood pressure, heart, back or neck problems, motion sickness, or other conditions that could be aggravated by this adventure. Expectant mothers should not ride.
Those rides include (but aren’t limited to… if in doubt read the sign at the ride entrance)
Soarin, Barnstormer, and Seven Dwarfs Mine Train do NOT have that warning on the website.
“Health and temperament” - that’s what I meant by “depends on your mom” but you said it so much better! 
I took my parents to DL when they were in that age range. Dad who has chronic back and heart problems (and who was actually in much worse health than he let on to) rode virtually everything with me and had a great time. Mom, who was in generally excellent health, rode nothing more adventurous than POC or HM. It so depends on the individual…
Imagine my horror when I found out 3 months later that Dad had unstable angina and needed a quadruple by pass - and I took him on SM, BTMRR, and the Matterhorn…
Does your Mom visit the doctor regularly or will she have a recent check-up before your trip? Not to sound any alarms or make her worried, but if you know that she has a decent history of going to the doctor, then that should help to lessen either of your concerns. On the other hand, if she stays away from the doctor, it might be helpful to try to get her in for a checkup before your trip. You could easily have the conversation in advance because it relates to your trip planning. You could say that you are trying to start figuring out the daily schedules & Fast Pass choices, and has she thought about what rides she might like to do? If she’s unsure about them all, you can read some descriptions & include any warnings the ride has.
I bet you will get an idea of what she might be up for, and if she seems hesitant to ride something yet is in good health, then you can start to work on convincing her how awesome it will be. Good luck!
I’m in early 60’s and in fairly decent health, no back problems. Last summer I rode every wild ride, with no problems at all. The one I thought the roughest was Space Mountain, and it’s not on your list. Dinosaur is also fairly jerky, but not on your list. I’ve never been on Barnstormer because it seems like a kiddie ride, and didn’t exist when my sons were young, so I can’t speak to that. I loved Tower of Terror, which is mainly just a lot of straight up and down lifts/drops. Expedition Everest was fairly smooth (compared to Space Mountain). Splash Mountain’s only hazard is getting a face full of water if you are in the front row like I was. I agree your list should be very doable.
Thanks for your replies! It really helped me figure out FPP for my mom. I think she will be alright on the stuff I had planned for her I’ll just have to skip FOP since there’s not much said about it.