When I look in my preview render everything looks fine (for not having finished lighting) but when i actually render it the color of my doughnut icing glitches and the texture of the table doesn't appear.
It looks to me like you have some extra lights and meshes in your scene that are hidden in the viewport. Objects that are hidden in the viewport won't show up in the preview renders, but will show up in the final renders. You can reveal any hidden objects by using AltH. Then once these hidden objects are revealed you will be able to see their effects in realtime and remove or adjust them accordingly.