The yellow onion is perhaps considered the all-purpose onion no matter what you wish to do with it. This would definitely be considered a safe bet. White onions can also be used, and although it has a strong taste when you first bite into it, it is the one variety where that taste disappears faster than the others. If you like onions but not too overly pungent, especially when eating it raw, sweet onions may be the best choice for Korean pickles. These would include Walla Walla, Vidalias and Mauis. These onions are also perfect for salads. If you love peppery and spicy, red onions are fantastic. In fact, in Western pickling, red onions are more popular than yellow or white onions. They do also look great.