I beleived that vodka was a grain spirit, but I bought a bottle of Asda's own label vodka and it read that it was distilled fom mollasses. which is the better type mollasses or grain?
The best Russian vodkas are made from wheat, but Caribbean vodkas are made of molasses (from sugar-cane). Since 'vodka' is itself actually a Russian word - meaning 'little water' - maybe you should consider that country's version as the model of perfection, just as one probably would re whisky and Scotland. (Potatoes are used to make the spirit in Poland.) For more information on the topic, click http://www.tastings.com/spirits/vodka.html
QM even as a Fellow Scot, I am afraid that you may have to allow some leeway on the Whisk(e)y one.....the world's oldest distillery is in Ireland after all at Bushmills.