Blue and white smoke when cold startup

I own a 2009 Toyota Corolla. I
purchased the car with 80000 km on
it and have put on mileage that now
totals 320000 km. I noticed this
morning that when I started it up I had
quite a large puff of both blue and
white smoke coming out of it the
exhaust that is. Can someone
possibly tell me what it is and what
the cost would be roughly to fix that
problem and or is it even worth it. I
have always change my oil at 5000
km without fail since I took it over and
then I change the every 3000 km. I
have not always used a synthetic oil
but I have used on some occasions
Lucas. I haven't used Lucas in a while
would I notice a difference if I started
using it again.