The Kana-to-Kanji dictionary list dialog (see Figure 1 below) is used by the Japanese input system when you enter Kanji. Thus, changing the dictionaries in the Kana-to-Kanji dictionary list will change the entries found when you trigger Kanji searches in the Input dialog (the Input dialog is the floating window used to enter Japanese).
Note: Most users add the Edict reference dictionary to the bottom of the Kana-to-Kanji dictionary list. Edict is a general reference dictionary which contains over 60,000 entries, which makes it very useful for the entry of Katakana words and Kanji compounds. This dictionary is available free from the www.lavasoft.com web site (in the JWM users area), and is also included on the JWM Companion CD.
You should never need to remove the Kana conversion WNN dictionary from this list, since it is central to operation of the new Japanese input system. However, you may wish to create and add your own custom Kana-to-Kanji conversion dictionaries to supplement the entries in it.
You may wish to look at the full list of JWM dictionaries available.
Classroom Edition
When running JWM as a student, check the checkbox titled, Use list on Teacher's hard disk to get the fastest Kanji input searches. When this checkbox is unchecked, dictionaries stored in your student folder will be used instead. If these are contained on a floppy disk, searches will be much slower.