AFAIK there are two main types of diesel.
The stuff sold in gas stations, which works fine. Also called on-road or clear diesel. It's what I have been using in my Westerbeke for 10+ years.
"red dye" diesel. Very similar to the regular diesel, but cheaper, as it is tax-exempt. If you put it into your car and it is discovered, you may get a fine. But in your boat it is legal.
There is also #2 diesel, normally used in long-distance trucks, and biodiesel. #2 diesel (I am told) will work fine, but has a lower cetol rating and so will be more difficult to start, especially in lower temperatures.
I have no experience with biodiesel.
One other tip - you may want to consider a fuel additive. Depending on how long you leave fuel in the boar, some algae will happily start consuming the fuel (!), and some stabilisers also improve starting. Personally I use biobor JF - but I am no expert!