Pointers for shoot...?

[jcuknz]

The modern camera is a wonderfully helpful tool and often knows more than its operator so if you do find yourself in a contrasty situation do not be afraid to use the onboard flash. The main problem here is that results will look like a flash photo so the simple solution is to tell the camera to reduce the power of the flash relative to the ambient light.... read the manual for info about adjusting the on-board's strength and set it to minus one stop for starters and if that is a little strong then a bit less. Something like minus 1.5 stops is usually quite pleasant and inobtrusive for head and shoulder to waist shots.
Having the light to the side or behind the talent makes for a better shot if you know how to handle it ... if you don't it is likely the camera will once you tell it the light balance you want.

I would have thought either lens would be good for portraits although with the 55-200 you could zoom out a touch. As for wanting to work at large aperture for out of focus backgrounds I would suggest unless you have done a lot of this you forget about it and work at a more tolerant f/5.6 and get photos in focus. It is so easy and quick to put backgrounds out of focus in a proper editing programme I don't see the point is risking having focus in the wrong place when working at large apertures. Of course if you want to do this you have to start sometime, but preferably not on a 'job'