Providng the oil meets the standards for whatever engine you put it in it will be fine.
Don't forget to flush the old oil out with water though.
^^ Its just like that to make it easier for people to decide what to buy. Most of them are the same oil in different packaging and if you look on the back they will meet the standards for petrol and diesel engine oil.
However there will be some oils that are just designed for use in diesel cars as they will not meet the standards for a petrol engine. PM oilman if you you want a more detailed answer!!
spot on.
Tescos 15w40 diesel oil meets surprisingly high standards. Way too thick for a clio though