Bubbled peeling paint
 

Water leeked down dry wall and some of the paint bubbled, part of it peeled a part rippled, how do I get the wall ready to repaint?

Scrape the paint and see if any damage was done to the drywall. If not, scrape it real good to remove all damage, float it smooth, texture if that applies, then prime and paint.

Be sure to prime stained area with a stain killing primer.
Brushjocky will say Smart Prime, Bin will work also.