BP Oil spill

If BP goes wonky, does that mean the UK govt will underwrite everything and monies will be guaranteed?

Not sure, unlikely.
Insurance will cover it though, and BP have massive insurance.

Yeah I'm keeping an eye on them though. The only thing which bothers me though is will they ever fully recover from this? Surely if they owe this much money it will take them a long time

They will, bigger shit has happened to other oil companies.
it will take time.