TOBI IS NOT OBITO and here is the reasons why
1st - in the kakashi's past arc tobi was crushed by a boulder on his right eye and he had his left eye removed, so in fact if obito were to be alive today he wouldn't have any eyes what so ever. on top of that obito had a cry baby like type of personality and a serious one. tobi has on the other hand has a care free and joking type personality.
2nd - Tobi's mask has a hole in the right part of the face we can assume that is his eye but obito doesn't have any eyes what so ever because of the incident. if he did have a remaining eye he would have given it to Kakashi instead of only 1 eye.
3rd - obito was at the time a genin or chuunin we can assume because kakashi was basically the leader of the group as the 4th commanded. and because having half your face crushed under boulders and having an eye surgically removed atm will kill anyone. better yet his whole body basically was under enormous boulders. including his RIGHT EYE. and most likely w/o help a chunin or genin will pretty much die. and obito was anyone trully skilled we can assume.