yes he could transform into the fox like form (im guessing u mean the one when he was fighting gaara) because he only had to think of it.

he would be able to summon but not summon gamabunta. he wouldn't be able to heal himself like kyubi does.

but every time kyubi does these things its going INTO NARUTOS BODY.

we don;t know if its the chakra that heals naruto, kyubi does that against narutos will be he still has to renegerate cells in order to heal.

also on a side note i don't believe that the energy only comes via the heart. the fight with neji. one of the points he hit was the heart and around it (if i remember correctly). if it is so then reguardless of kyubi he couldn;t send chakra, thus the only alternative if this is true is that kyubi can directly give it to the body of naruto.