For your chips and your junk food head for your local snackbar. To help you find your way: Dutch chips are skinny and crisp, Belgian chips are fatter and better. The Dutch call chips patat and crisps chips. Just to make bilingual life complicated.
For the unintiated:
Patat met: chips with mayonnaise
Patatje oorlog (war chips): chips with mayonnaise and saté sauce (Dutch versus the Indonesians)
Patat speciaal: chips with tomato sauce, mayonnaise and raw chopped onions
A kroket is rissole with a vaguely meat filling. Eat with mustard. A fricandel is a fried thingie which once looked at a cow and a horse at the same time. It's the ultimate in "recovered meat". Avoid like the plague
The best chips in Amsterdam are to be found on the Voetboogstraat, just off the Heilegeweg.