http://mario.soniccenter.org/rankings/rulesStatistics are taken from the time the timer stops. This is usually when the signpost, goal ring or the capsule is hit, though in some levels it may apply to other events, eg. in Wing Fortress, time is taken from when the screen fades out. Scores are taken after all the relevant act bonuses are added.
Hur hur signpost, goal ring, capsule and Wing Fortress Zone.
Using any method to reset the timer to zero in the middle of a level is not allowed.
Well that would be pretty stupid as 0 is like the worst time you can get.
Unofficial emulators that do no replicate correctly the original gameplay are not allowed. This currently spans DS, Dreamcast and any newer non portable consoles, and more.
Hur hur Mario on Dreamcast.
For ring stats, you may not collect the same ring(s) more than once.
Hur hur rings.
Wii Virtual Console remake
It's not a remake, it's just emulated.
PAL versions
I'll check the timers of my SMAS version to see if SMW is not the only game affected. Also I could check SMB NES but I'm too lazy to connect the thing.
And this point needs a better solution. Banning everyone from Australia and Europe isn't really pleasing.