Corrected your image for you.
Your printer uses magenta, yellow, and cyan ink to make all the colors of the rainbow, not red, yellow, and blue which these colors appear to be similar to. Magenta, yellow, and cyan are the primaries of paint and are the opposites of green, blue, and red which are the primaries of light. This is because pigments work by absorbing color, so by absorbing red light, cyan pigment leaves a cyan reflection. This is basic physics. Why they lie to you in elementry school, I have no clue.
For the questions:
There is no need for title. The original purpose for the title in vB was to display staff status. Since we use the staff icons to do this, there is no need for the title field. There is plenty of room in your signature and avatar for personalization.
The join date has been converted to longevity, which will show the percentage of the board's existance that the use has been a member. The actual join date will be displayed in a tooltip on mouseover.
vB3 is threaded board software. All replies are made to specific posts. The reply button does quote, but there is no reply to thread button as it exists now, you reply to a post. You can choose a thread view that lists all the posts as what is replying to what. This is also why each post has a quick reply button, and what the link next to the post title is about (click the link to see the post that was replied to). The post padders should like this as it gives them an excuse to double post if they have something to say to two different posts. Chruser wanted to try this, so we will be using threaded mode on a trial basis; if we decide we don't like it, we will convert the board back to linear mode, and reply will change back to quote, etc.
Online is whether the user is online, recent is whether or not you have read the thread since the post was posted.
The Today indicator is the stars that currently only you can see above your activity. If you enable invisible mode, the visit block will not be lit for other users untill your first post for the day. (If you posted, you've obviously visited. Curious users could just search to see if you've posted anyway.)
The icons at the bottom of the panel are fixed, but they will not all always be there. Guest posts (if we ever allow them) will have none of them. Member posts will always have the buddy and ignore icons, and will have the e-mail icon only if the user has set to allow e-mail through the board system (the e-mailer does not get your address unless you directly reply to them--you can use the forum to reply to retain annoymetiy) (I recommend against enabling this option if you're on the forum all the time, as we will be locking the PM system on with popup notification (note that if you ignore a person you will stop getting their PMs) so for most purposes, it will be sufficient). The IM program icons will only appear if you have entered your ID for these programs.