that is a difficult one!
It usually depends on the meal and also the sauce -when I used to eat meat, I would love to have a boiled potato, and mash it in the natural meat gravy.
Now that I do not often eat red meat, my sauces are home made and I probably like rice best as it is easier to eat than noodles, however I find I often make potatoes as they are quicker and can just be put in the microwave.
I like all three and recently made lasagna or spasagna (published on Recipe Yum) using noodles instead of lasagna sheets and it was DELIGHTFUL!
I always have rice or noodles with a meal with sauce. Asian stir fries which are vegetables in a sauce are always served with rice or noodles. Some casseroles with lots of sauce are always served with rice to absorb some of the moisture, leaving just enough so it is enjoyable.
I am very easy to please with all three of these items,as I enjoy them ALL!!!! When I have a roast with Pan Juice gravy(the ONLY gravy I like!!!)I cannot go past scrumptious roast potatoes,otherwise I really do not have a favourite between rice and noodles/pasta!!
I have noodles with stroganoff and rice with Asian food. If its gravy over meat then it has to be mashed potato but I think mostly it boils down to what our mothers served with our meals when we were growing up. Occasionally I will have a packet of savoury noodles with my meal for a change.