Sorry if someone has already mentioned this, but if you do have a car that is written off because of the cost of repair, then at a later stage the DVLA may ask you to take it to be inspected by one of their engineers, to check that it is the original vehicle chassis number, and not two welded together, which you have to pay for. The DVLA said that my insurance co requested the check, but they denied it, and the DVLA gave me a time limit when it had to be completed by. My local DVLA station could not do in the time reqired, so I had it done 250 miles away as that was convenient for me.
My insurance co was very awkward, demanding that it be repaired in a certain time or I would loose my insurance cover, and like the OP it had to be MOT-ed. it was a lot of hasel, the accident was my fault and if it happened again, I would not make a claim for my repair, in spite of the Insurance co giving me about £600, like the OP it just wasn't worth the hazzel.