First off, we'll discuss each bosses' fighting style, as it will come into play in a battle between the two. For the purpose of this match, we're assuming the bosses are meeting alone, on neutral ground, and neither come with adds.
Razuvious is a melee powerhouse who relies on brute force to win his battles. He dishes out physical damage in astonishing quantities, with his Unbalancing Strike ability hitting for more than most players' health will allow them to survive. However, Razuvious doesn't really have any tricks beyond his overwhelming melee damage -- which may not be as overwhelming to another boss such as himself.
If you're curious about the full details of the Instructor Razuvious encounter (there's a lot to it we haven't discussed here!), check it out on WoWWiki
Precisely unlike Razuvious, Ragnaros doesn't rely on melee damage to bring his opponents down, but instead overwhelms his enemies with massive amounts of fire damage. He has a nasty knockback (in fact, multiple types of knockbacks) that will hit his targets with fall damage as well as a high-damage fire DoT. And finally, he damages melee weapons that hit them -- eventually causing them to break.
There is, of course, much more to know about the Ragnaros fight than what I'm mentioning here -- but it primarily involves adds and raid positioning, and wouldn't have any impact on a one on one fight. However, if you're curious about these things, check WoWWiki
So the question is -- who would outdamage who first? Would Razuvious bring down Ragnaros before Ragnaros melted his sword? Or would Ragnaros simply be overwhelmed by Razuvious' melee damage? Before you answer this question, we're presuming that both of these bosses are approximately the same level and strength. But comparing their fighting style, who do you think comes out on top?
I'm afraid voting for this week is over -- but be sure to check out the wrap-up
to see how it all turned out!