Oi!
The room lights should not effect the tank. Yes when the tank lights are off there will be 'light' going into the tank but it is minimal compared to what is above the tank.
Ambient light from windows [NOT WINDOZ 95, 98 2000 XP or NT, HA!] will only effect the tank if it is 'bright' enough to offset the tank lights, most room lights are NOT that bright [I hope unless you live a landing pattern at O'Hara, HA!] Personally I think that the fish like the 'view' looking out, so they can see us in 'our tank', HA!
I've had good and bad luck with direct sunlight from windows, my 5 gal. starter tank never minded it, but my 29 Rock tank did have an algae bloom, but it was mostly my fault when I wasn't watching the water movement and prams. Before they [prams] went Wacko! I never had a problem and the coral on the rocks were doing fine.
Cheers!
nigle
!~!