Are France and Russia becoming Allies?

To some degree the answer might be "YES".

This also might lead to something we experienced in the U.S. alliance with Russia during World War II which was against Hitler and Tojo who were common enemies of Russia and the U.S.

However,now everything is different in that it is ISIS we are talking about aligning against now. Also, this is very complicated because although France and the U.S. and NATO are all against ISIS they are not against the anti-Assad Democracy activists fighting Assad that Russia is also bombing. So, this part of the equation is very troubling for Europe, the U.S., France and most of the rest of the world.

Will this prevent a nuclear war with Russia in the future? Yes. This is likely so.

However, it will not prevent an ongoing Cyber war between the U.S. and Russia alongside China.

Ted Koppels book
"lights out" is partly about this. Even though terrorists are more likely to do this in the end than Countries would be for a variety of reasons.

Is it a good thing if France and all NATO countries  and Russia eventually align against ISIS? Maybe.

In the short run this might be good. But in the long run if Sunnis in Syria and Iraq still don't have any rights (like the right to stay alive)  then this could be really really bad in the long run on many different fronts.

So, if ISIS as a country is gone but ISIS as a terrorist organization like Al Qaeda is still around then this is going to be very bad for the next 50 years or so for the whole world or more.