Login information  
User name:   The name you want to use on the board.
Password:   Enter any password up to 32 characters in length. It can later be changed by editing your profile.
Appearance  
User picture:   The full URL of the image showing up below your username in posts. Leave it blank if you don't want to use a picture. The picture is resized to 60 in width. You can also select from a limited set if you want to.
Minipic:   The full URL of a small picture showing up next to your username on some pages. Leave it blank if you don't want to use a picture. The picture is resized to 11x11.
Post header:   This will get added before the start of each post you make. This can be used to give a default font color and face to your posts (by putting a <font> tag). This should preferably be kept small, and not contain too much text or images.
Signature:   This will get added at the end of each post you make, below an horizontal line. This should preferably be kept to a small enough size.
Personal information  
Sex:   Male or female. (or N/A if you don't want to tell it)
Male   
Female   
N/A
Real name:   Your real name (you can leave this blank).
Location:   Where you live (city, country, etc.).
Birthday:   Your date of birth.
Month: Day: Year:
Bio:   Some information about yourself, showing up in your profile.
Online services  
Email address:   This is only shown in your profile; you don't have to enter it if you don't want to.
AIM screen name:   Your AIM screen name, if you have one.
ICQ number:   Your ICQ number, if you have one.
Homepage URL:   Your homepage URL (must start with the "http://"), if you have one.
Homepage name:   Your homepage name, if you have a homepage.
Options  
Timezone offset:   How many hours you're offset from the time on the board (03-11-10 10:08 PM).
Posts per page:   The maximum number of posts you want to be shown in a page in threads.
Threads per page:   The maximum number of threads you want to be shown in a page in forums.
Use textbox toolbar when posting:   You can disable it here, preventing potential slowdowns or other minor problems when posting.
Disabled   
Enabled
View signatures and post headers:   You can disable them here, which can make thread pages smaller and load faster.
Disabled   
Enabled
Thread layout:   You can choose from a few thread layouts here.
Color scheme / layout:   You can select from a few color schemes here.