Modify Membership Registration and "My Account" Pages

How can I modify two of the auto-generated Membership pages:

1) Registration - Is there a way to get the page text (or any custom text) to appear *below* the registration form instead of only above it? We'd still like to have some custom text appearing above it, too, if possible.

2) My Account - how can we customize it to display (and allow users to edit) more of the standard WordPress profile fields (e.g., website, bio, gravatar) and even a few custom ones (e.g., Location, Image).

Thanks much!