What settings should I set my Nikon D90 for in-house photos of my newborn baby?

I would like to take my own pictures of my newborn baby, by placing pillows underneath a white sheet & backdrop. I'm not too sure on what to set my Nikon D90 to for THE BEST RESULTS.

When I take the pictures with the (A) setting & using an SB-600 flash, the white from the sheet is too extreme and ruins the picture. The flash is aimed at the ceiling, bouncing off of it & still looks way too bright. The room isn't the most lit room there's, but when I don't use a flash, the pics become too dark.

What should my ISO be set to?
And what should my White Balance be set to? ( I usually keep this at AUTO)

Because the room is not full of light, I've upped my ISO to 2800

I'm using the Nikon 18-200mm VRII lens as well.

ANY help or tips would be GREATLY appreciated!

Get yourself a 50mm/1.8 lens and/or use a more brightly lit room.

Do your baby a favor and do not use flash when it's around.

Oh dear…

ISO 400, Auto wb will do.

Set the flash in ttl-bl, cam in center metering. Start out with -1 on the flash and see what that does.

Do some test shooting on a stuffed toy or something and get ir right before you start on the baby.

You can tone down the flash by placing something in front of it. Such as a piece of tissue or wax paper…

50mm f1.8 is the answer, it'll be one of the best lenses you buy.