Doctor Who cannot be defeated!!!

Basically I love to have these geek debates in my head as to who would best the other in a fight. Right now the ultimate of all that I have found is Doctor Who. I've gone through so many scenarios in my head and can't see how he can be bested. For those of you who don't know the Doctor... "Doctor Who?"... Exactly... let me explain.

The Doctor is the last of his race of Time Lords who uses his T.A.R.D.I.S. (Time And Relative Dimensions In Space), a time/space machine, to make sure that everything that is supposed to happen in the past/present/future happens as planned. Other than time, space, and dimension travel he also has the ability to regenerate after death.  Whenever he comes back he takes on a new look to make sure the show continues. He also has a handy device which can interact with any technology called a sonic screwdriver.  It's only weakness is it cannot affect wood... tee hee.

Having the ability to pretty much not die and time travel makes you pretty much a Gangster in the epic battles that go on in my head. Lets go through some of the match ups I've gone through... Doctor Who vs Super Man... Superman may be fast, strong, able to fly, have laser vision, and impervious to bullets, but there is one minor flaw the little green rock (Kryptonite you jerk). All doctor who has to do is go back to Krypton before it explodes and make a krytonite cage... or even better when it's that time where superman is sent to earth as a baby he can redirect the shuttle to another earth like planet that does not have a red sun.

Ok so that's settled next try Batman... Super smart, always prepared, world's greatest detective, and is driven by the death of his parents to bring justice to his home town Gotham.  In that last sentence is the answer to the question... Stop Batman's parents from dying then he will never become Batman and have that driving force which made him who he is. Not to mention any gadget he can think of using is stopped with the sonic screwdriver.

Next stop the strongest in the Marvel Universe... The Doctor vs The Hulk... The Hulk is the scientist Bruce Banner who was part of a gamma experiment gone wrong which turned him into the monster know as the Hulk. Need I say more, why face the hulk head to head just go talk to Bruce Banner before he even takes part in the experiment... I'm sure he would have no problem with being a normal scientist as apposed to a raging monster who can't die.

My Point to all this being Doctor Who is unbeatable...

Point Blank

SMD!!!

Hit me up with a possible opponent so I can find a way to defeat him.