Java + Itex + Jasper Reports

[Anceschi Mauro]

Hi everyone!.
I'm about to start a new project where I'm must create a documents
editor (ala Word) where multiple user can access paragraph information
viewed with a tree:

Manual
|-Chapter1
|-Paragraph1
|-Text Block
|-Text Block with image
|-Table

Two question:

Since i need to store data on a database i need to store every single
block on a TEXT ( assume use mysql) field. Wich is the best way to
store information foe every block? XML, HTML or custom data format??

I need to create output for rtf and pdf....since the software will'be
created for document editing, what librery should I use? IText? Jasper?

Thanks in advance.