Katie,
When I left Lenox Hill after my 6 day stay, I hired a car service & paid $225 for the 2 hour drive home. There was absolutely no way I would have been able to handle the 15 minute subway ride & then the almost 2 hour train ride home. The subways in NY are usually jam packed. Especially on the Lexington Ave. Local. I've been on the subway, with my cane, & never once did anyone ever give up their seat for me. Sad society we live in.
I was told that it was not advisable for me to be sitting upright for the ride home. I was told to sit in the front seat & lay the seat back. Of course I didn't listen
Since I'm short, I was able to more or less stretch my legs out while sitting semi-upright in the back seat. I had my husband bring down some pillows to prop up against my upper & lower back to keep my spine straight. We had a town car so it was comfy & the driver knew I just had spinal surgery & he did everything he could to make the ride as comfortable as possible.
You should also know that with lumbar fusion, sitting tends to be more uncomfortable than with ADR. If you are "blessed" like I was & have incisions in both your belly & back, it's going to be tough to get comfortable.
As for seat belt laws in NY, if you are sitting in the front seat, you have to wear a seat belt. As far as I know, if you are sitting in the back, it is not required. Just make sure you don't play Super Woman if your husband hits the brakes!
There is an "AirTrain" from JFK airport to the local subway. You just have to figure out which line to get on to take you out to Lenox Hill. I'm not very city savvy so I won't even venture to guess on that one.
My sister has flown to Toronto a few times for work. I can see if she may be able to suggest any low cost carriers for you.
Sorry I can't be of more help to you.
Karin