Help. Blue smoke on tick over, goes when car is moving

[andy007]

Blue smoke on tick over, goes when car is moving, it seems at lights or tick over smoke comes out the exhausts. Its an old Ford V6 3ltr essex engine, i had the hardened valve seats fitted 8 years ago, just changed the oil to magnatec, any ideas. It also runs rough for a few minutes if you turn it off and restart it about 5 mins later ?