post some pic... if im not wrong, the indoor shot grains was cause by high ISO, while the underexpose of outdoor scene is cause by high dynamic range, where the sky is much brighter than the surrounding.
to counter the outdoor problem, you might want to increase ur exposure-compensation or meter on the surrounding rather than multi meter on the whole frame... but this will also mean you get a fully white sky most of the time.
for indoor, if possible set the ISO yourselve instead of letting the camera decide. place your camera on a stable ground(tripod/table...etc) since long shutter will have to be used, other than that i don think you can really do anything to it(without flash) unless you change to another cam...