If Russia is serious, they can start by joining the coalition in Iraq. Once stable, on to Iran and Syria.
Not sure we want Russia getting involved with Iraq... don't need the "we'll take over from here" mentality creeping in like it did at Yalta.
And no, I don't trust Putin further than I can throw him.
I don't think Russian troops would be welcome in Iraq by the US, the UK, the Turks, the Iraqis, or the Kurds. They could come in very handy, however, for the coming storm in Iran.