Turkey is in NATO, guys. Their planes are NATO planes.
Al Nusra(FSA buddies? Anti-ISIS? Anti-West)
Jabhat Al-Nusra is an offshoot of Al Qaida in Iraq, the predecessor of Daesh (ISIS), which refused to recognize the authority of Baghdadi when he declared ISIS. It's still aligned with Al Qaida. This has resulted in Al-Nusra and Daesh fighting, but they've also cooperated at times. It probably depends on the commanders on the ground.
This article on the history and origin of Daesh also talks about the origin of Al-Nusra:
http://www.vox.com/2015/11/19/9760284/isis-historyKurds(Rebels? But friendly with regime? and the West? More interested in self preservation...)
There are Kurds in Iraq, Syria, and Turkey. They'd like to have their own state - Kurdistan - rather than just being a minority in other states. Turkey isn't likely to oblige them but there's nothing to stop them from doing that in Iraq or Syria now. They're more focused on fighting Daesh at the moment, though.
The ones in Turkey (The PKK) are designated a terrorist organization by the US and others. After joining the war in Syria, Turkey treated even the Kurds in Syria as their enemy, likely out of fear of them joining with the PKK to try to establish a unified Kurdistan that includes Turkish territory.
Iran/Iraq(Married to the hip with regime, well they definitely got boots on the ground.)
It's important to note that the help Iran is providing are all shi'ite militias, much of the Iraqi military is as well, and the great difficulty they've been having is retaking sunni areas without alienating the population, which is difficult when your troops exact retribution for Daesh's crimes on the citizens who merely lived under their rule and managed not to get killed (by being sunni or christian and following their strict 'moral' laws, etc).
My understanding is that there aren't really any "moderate" rebels left, or at least none who aren't unaligned.
Helgoland: Obama's blowing up all of Daesh's fuel transport trucks. I think he's being called weak because he won't flatten the cities Daesh is occupying and kill everything in their territory with no regard for civilian casualties, like we did in WWII.