I have put disc in for 2015 tax year and not able to pull up my return that I completed and filed last year

The disc does not store the return. The return would have been saved to a computer or a removable storage device such as a flash drive.

Computer crashed in July and I lost all data so if I buy 2016 turbo tax my 2015 info will not be there.  will i have to start from scratch as if I have never filed with turbo tax

Yes you will ... you could recreate the 2015 return then transfer in that ... but going forward always save the PDF & .taxfile  on a separate medium so you don't run into this issue again.