ok, now first of all...

have you checked serviceable items, such as oil filter, air filter, oil level, coolant level?

my next step would be to check the throttle body, just to be safe, for any obstructions or for any gung that could be clogging it up and making the butterfly valve stick.

there is always the good old MAF issue (do a search on MAF..theres loads of threads on here about it), but i doubt that would cause a spontenous cut out, could be worth a check though.

there have been a couple of threads recently about the oil warning light and cars cutting out, ill try to find them and collate them on here for you