Well, I guess the biggest question of all is are you going to be moving the camera?
I would really suggest you "lock-off" the camera, i.e. set it on a tripod, frame your shot, and shoot.
Then extend your matte if needed by shooting high-res stills, nodal pans of the camera for extra fill footage, or straightup paint.
As far as the 3d interaction with the water surface, fluids are probably not your best choice here.
Despite its' name, fluids are better suited for gaseous effects rather than flowing water type effects.
That is where products like RealFlow come into play.
I would suggest nParticle water (Maya 2009), hardware particle spray, 2d and 3d projection to achieve the initial bulge of the object breaching the surface.
As a compositor, my first impulse would be to use multiple types of water plate footage from a high frequency waterfall with different time offsets etc. projected onto the rising geometry, along with hardware particle spray to augment the falling water off the object.
Does any of that help?
Israel "Izzy" Long
Motion and Title Design for Broadcast-Film-DS
izzylong.com