The most difficult for most English speaking people is words with lots of G's or some place names like Scheveningen or S'Gravenhaag.

The Dutch on the other hand sometimes have problems with the "TH" sound in English.

Easy word 's to start with are
Dank je wel ( pronounced dank yuh vel) it means thank you
Alstublieft (als tuh bleeft) it means please (literal translation would be if you please)