However, my thoughts:
If Revan was capable of having nearly a perfect win record over the Mandalorians, and utterly crushed the Republic and the Jedi Order during his reign as the Dark Lord, he should have no issue with the Separatist, and slay Dooku (or get a strike team to do it) as he did to Mandalore.
In terms of saving Anakin, I say yes. Revan is very well known for his charisma and his ability to either corrupt/redeem people. If he was able to persuade majority of the Jedi to join him in war, corrupt a portion of the Republic's entire military, and redeem various individuals like Bastila Shan, he shouldn't have that much issues with Anakin.
However, even if he defeats the Separatists, the true problem would be with Palaptine. Via his extreme precognition which is capable of predicting stuff months in advance, he can probably figure out when Palpatine is going to commence his Order 66, however thanks to Palpatine's "clouding minds with the Darkside", I doubt Revan will realize until it's to late. It really goes down to what Jedi are on Coruscant when Revan is forced to confront Palpatine.