When people make an account///

They have to fill up so much, where can i change it? I need only, Email, password X 2 and capcha.

You can make a quick join form with only the few fields you wish at join time.  The profile edit form can then contain more items that the users may with to fill out later.  This is done with the profile fields builder.  The builder has three settings, views for guests, views for users, and views for admin; that controls with each of the three will see when visiting the profile.  When I first started using Dolphin, remembering to click into the view I needed to work on was something that I forgot.

Keep in mind that these fields are required:

• NickName (Username)
• Email
• Password

So you need at least those three on the join form for things to not break horribly.

Go here www.yoursite.com/administration/fields.php

Also keep this as Nathan said :

Keep in mind that these fields are required:

• NickName (Username)
• Email
• Password
  
  

Cool, it's ok.

How can i make mandatory that they must upload a picture?

thank you in advance.

There's a few threads in the forums that cover this. One result: http://www.boonex.com/forums/topic/Mandatory-profile-photo-.htm#198689

Note that you'll likely have to clear Dolphin's cache after making these changes.