As has been said many times before, each case is different and each individuals circumstances are different and therefore it is impossible to put a value on your claim other than to say it will be quite substantial.
However, because you have admitted that you were not wearing a seat belt, the value of your claim will take an immidiate hit up to a possible 25% on the value of your cliam for contributory negligence.
You can still make a claim via the MIB which handles unisured or untraced victims, but a couple of things you need to bear in mind.
One of the questions asked will be were you aware that the driver was uninsured? From your second post I would say that is a no brainer, otherwise you would not have posted your comment.
Secondly, have you reported the driver to the Police? One of the MIB protocols is that the Police are notified and you may not be happy about shopping in a mate or whatever.
Either way, you will need to get help from a solicitor who has specialist knowledge of how the MIB claims system works.
Do not go to one to one of the claims management idiots who prowl these boards, they will simply sell your case to the highest bidder and you have no control over who handles it.
If you want a recommendation, then drop m a line, but if you use any of these idiot claims management firms who are all touting for business on this forum, your claim will be undervalued before you even start.
There are many specialist solicitors both here and in your own area who will have the MIB specialist knowledge, give one of them a call, they will be happy to come and see you without obligation and get the ball rolling, or as I say, drop me a line and I will be happy to point you in the right direction.