Photos coming out with too much yellow

The first solution is correct in that the problem is definitely white balance... Are your indoor lights tungsten bulbs, or florescent bulbs that use less energy? They give different light, and you need different settings.

To manually set the camera to balance the colours in incandescent light (i.e. tungsten light bulbs) or indeed several other light sources such as raw sun, shaded sun, cloudy day, you look for the WB button on the back left side of the camera. (I have a D70 too, I know it's there, second from the bottom.) Holding that button down, twirl the thumbwheel (rightside top/back.) Look in the top LCD while you're doing this, and you'll see icons for the various preset white-balance profiles. Try them all out -- it's interesting to get a feel for how blue sky makes everything bluer.

The amazing part is that your brain and eyes do all this for you without effort. :)

Hope this helps.

You're shooting under incandescent light, and the camera doesn't manage to set the white balance entirely automatically. You can try to explicitly set the white balance to incandescent, or you may be able to create a custom white balance (I'm not sure whether Nikon bodies offer that feature), or you can adjust the white balance during processing (in which case it's better to shoot raw).