At that distance, 1080p would not be discernable until about 50" TV.
Your question which size for that distance, generally it is 1.25 to 2.0 times the screen width (can be a preference)
But by optometrists point of view, if I recall correctly they prefer the 2.0 distance for safe viewing.
That being said, 1.5 is the norm.
So 32" will actually be small. 42" would be ideal 46" would not hurt, and 50" is kinda pushing it (IMO).
LOL, however, I watch a 50" at 8', the 42" at about 9', and the 96" at 12'.
So no worries on being to big with 32", your eyes will be quite safe at that distance, and 720p would be all that is needed (for TV and movie watching).
But if you find a deal on 42" (or 46") 720p, I would suggest not passing it up.