The Battle of Cheron started with 81 Romulan ships and 24 Earth ships (1 NX, 3 Daedalus, the rest probably Delta/Emmette/Neptune class or ?DY-500).
Where are you getting this?
^What Timo said.
I have taken it from "To Brave the Storm". The numbers were directly stated there. And here I am paraphrasing the 20 ships were described as older. This, along with the fact that Archer had to beg and call on favors to assemble this task force would indicate what type of ships they are.
It is possible that there could have been some Intrepids, but I doubt it. And the Warp Delta and DY-500 were the other other fight classes mentioned in the current continuity.
I suppose it is possible that ships from Star Trek Legacy (like the Strider, Discovery, ... classes) were involved, but I did not want to open that can of worms.
If nobody wants to try, here are my estimates (+/-5) before the war
Romulan Star Navy size: 310 vessels
Vulcan Defense Command size: 100 vessels
Andorian Imperial Guard size: 160 vessels
Tellarite Stellar Navy size: 120 vessels
Klingon Imperial Navy size: 205 vessels