minimum word length
Default: 1 letter. When making a word-list, you can specify a minimum word length, e.g. so as to cut out all words of less than 3 letters.
maximum word length
Default: 49 letters. You can allow for words of up to 50 characters in length. If a word exceeds the limit and Abbreviate with + is checked, WordList will append a + symbol at the end of it to show that it was cut short. (If Abbreviate with + is not checked, the long word will be omitted from your word list. You might wish to use this to set both minimum and maximum to say, 4, and leave Abbreviate with + un-checked – that way you'll get a word-list with only the 4-letter words in it.
Default: 1. By default, all words will be stored, even those which occur once only. If you want only the more frequent words, set this to any number up to 32,000.
Default maximum is 2,147,483,647 (2 Gigabytes). You'd have to analyse a lot of text to get a word which occurred as frequently as that!. You might set this to say 500, and the minimum to 50: that way your word-list would hold only the moderately common words.
type/token mean number (default 1,000)
Enables a smoothed calculation of type/token ratio for word lists. Choose a number between 10 and 20,000. For a more complete explanation, see WordList Type/Token Information.