Given that their in a city with a large square area some advantages shift to the individuals highly trained in stealth combat and marksmanship such as Bourne, Ra's, Punisher, Robin, Hawkeye, Bullseye, Rambo, and even Predator (due to his cloaking device).
First lets start with the guys we can eliminate right from the start in order to narrow the field. These guys have no chance IMO:
1. Brenden Fraser (from the Mummy)
2. Vin Diesel (XXX, a better choice would have been Riddick)
3. Indiana Jones
4. James Bond
5. John McClain
6. Commando (Arnold)
So... we have left:
1. Rambo
2. Punisher
3. Jason Bounre
4. Robin
5. V
6. Predator
7. T-1000
8. Bullseye
9. Ra's
Due to a lack of durability and stamina I am going to further eliminate:
1. Rambo
2. Jason Bourne
We are down to 7
Once the shit starts to hit the fan, and it becomes more of a battle field rather than stealth warfare these next few guys will die in the destruction that ensues.
1. Robin
2. Punisher
3. Bullseye
4. Hawkeye
So we are left with three:
1. Predator
2. V
3. T-1000
V IMO does not have the means to do enough damage in order to take out the other two. So after a long bloody battle V is the next casualty.
The final battle IMO goes to Predator simply because he can cloak, and has the weapons to terminate (no pun intended) the T-1000. His plasma cannon can probably reach temperatures high enough to vaporize the T-1000.
Predator wins Majority
Of course this scenario is subject to different results pending various situations which could alter the outcome.