Do I need to sue for my benefits or discrimination?

I have worked for this company for 8yrs at various studios in the area.
In Aug 2005, I returned to my home studio where I was the studio manager.
The 1st company got aquisition by another company whose sales techniques different. I had no problems with the new techniques, I liked them.
This is were thing got funny.
Customers would recieve calles about the service.
Well to cut it short, I began getting write ups for low sales.
It was getting harder to make sales.
In March 2009, the regional director met me at a re-training sales meeting.
My distric manager was told that I was non-personable and this was not the job for me.
The Saturday before Easter I had a low sale day as I have been. Easter was a high sale day.
I recieved a call from my dm about the sales for that Satuday.
She suggested that since I had some vacation hours to take them and give a 2wks notice otherwise I would have my last write up which would mean I was termanated. (The funny thing is that the next Saturday with another manager, who sales are higher, made an even lower sales. It really doesn't matter who is there the sales could be low.)
Now after recieving a letter from the appeals tribunal, I may loose my UI.
I do have degenative back disorder which is genetic. I didn't hinder my work since it was a creative career.
What do I need to do? Sue for my job back? I really have out grown retail studio work and begining the process in opening a business.