[balinor]

You can turn on/off fields in General Settings/User Profiles options. I always combine the contact/personal info fields by editing customer/main/register.tpl and moving them one below the other. Then you go into main/register_personal_info.tpl and remove the header.

As for removing shipping, it is dangerous as people may want to ship to their work address or send a gift. Removing it may lose you some sales.