Characters who are restored to live by raise dead, resurrection or a resurrection effect such as a rod of resurrection lose 1 CON permanently.2) Since reincarnation changes ability scores, the CON loss is not considered, though the above rule regarding original CON is still relevant.
Being raised by a wish does not cause CON loss, nor does it count against times raised.
Elves and half-orcs cannot be affected by raise dead or resurrection3) because they have spirits, not souls.4) The soul or spirit is the unchanging thing that travels to another plane after death, and that which is returned when the creature is restored to life. Therefore, even if an elf or half-orc is reincarnated into a human, the character does not become eligible for raise dead or resurrection.
Unless the ability explicitly says so, the creature does not change form upon death.5)
Whether a creature can be raised from the dead by raise dead or resurrection depends on its original form. For example, a human druid who died while shape changed into giant bat form could be raised, but an elven or half-orc who died while polymorphed into a human could not.6) When the creature is raised, it will remain in the form it died in (including wounds and poison, as normal, unless the means used to raise state otherwise).