Lets see.. This is how I did mine..You hit the innkeeper, and t plays a music effect as the screen fades to black..then a save menu is shown and my party is healed completely...usually how most save/rest points work.
Make a new event, set the graphic to whatever, a bed or an innkeeper or whatever you want. Make sure you set the Trigger to 'Action Button'
[Edit] This is what should be in the event commands section, sorry I wasn't clear before:
Show Text: "Would you like to rest" (or something)
Show Choices: Yes, No
When [Yes]
Play Music Effect (or sound effect, or whatever)
Change Screen Tone (-255 -255 -255, 0 @ 20 frames) (if you want it to fade to black)
Wait (X) Frames (150 was enough to let the music effect play out for me)
Call Save Menu
Recover All:Entire Party
Change Screen Tone (0,0,0,0 @ 20 frames) (To fade the screen back in)
When [No]
Branch End