If I were the mission coordinator I would have snipers at every available window, ready to shoot any terrorist they see once a go code is given. (NOTE: If the terrorist was pointing a weapon at a hostage the sniper would have to shoot the terrorist an inch above the ear in order to stop the CNS instantly which will keep the muscles from contracting, killing the hostage.) Then I would take two three assault teams with silenced weapons (Probably MP5SD10, because of the CQC and high firepower). I'm sure everyone hear understands the concept of room clearing when there are hostages inside, but it would start with a charge on every entry of the room. If there were only one, then a charge would be placed on a wall to make another. The charges would stun anybody inside; giving the infiltrating teams time to engage. A second before the charges detonate I would tell the snipers to fire. I would coordinate the charges to go off once one of the snipers notifies me of a target in view. He would help that much more.
However, I’m just some kid that plays way to much Rainbow Six so I would had the job to someone else. Probably a highly trained hostage rescue team, probably some police division trained for hostage rescue, not a military team.