Does a 700c wheel go faster? Hmmmm...
Kinda hard to give a definative answer to this one as you have lots of variables to contend with.
Let's assume that both wheels being tested have the same mass.
Well a 700c wheel typically refers to a race wheel which is going to have a very high inflation rating and a thin profile. Both of these items allow for a very small contact point on the road (foot print). The smaller the foot print you have the less road resistance you will have and the easier it is to move the wheel along the road.
If it's easier to move the wheel along the road you can get a higher effiency power transfer to the wheel. If you have a higher efficiency then you waste less energy moving forward and so have more energy to go faster longer. So based on the sole assumption that the previous wheel has a larger foot print than the 700c wheel then I'd say that the 700c wheel does in fact have a greater likelyhood of traveling faster.
Now let's look at both wheels from the stand piont of 'moment of inertia' (MoI). That's the amount of force (torque) it takes to increase or decrease the rotational velocity.
If both wheels have a mass of 1kg and the 700c wheel has a radius of 311mm then the moment of inertia is calculated to be about 9.6kg m^2. If we compare that to a BMX wheel having the same mass and foot print (ya right, a skinny BMX tire?! Let's just go with it for the example) and a radius of 203mm we get 4.1kg m^2 needed to change it's velocity.
Moment of Interia Calculator
Theoretically the BMX wheel should be able to go way faster because it needs much less energy to increase it's angular velocity. The problem is what enables it to be able to accelerate so quickly is a double edged sword because it also allows it to be deccelerated just as easily.
Because we don't ride in vacuums, we need to contend with wind resistance as well as road resistance. So while it takes less than half the energy to get that BMX wheel up to speed, the counter effects of the wind and road resistance are acting at more than twice that of the 700c wheel at slowing you down. Also to remember is that the force from air drag is calculated from the square of your velocity so the faster you go the drag you need to overcome grows exponential. If you were thinking that you'll just go fatser to make up for the difference, think again.
It's a trade off. Do you want to be able to sprint up to speed really quick but have that speed bled off just as quick? Or do you want to be able to maintain your speed over longer distances, taking more effort to get up to speed, but be able to maintain it with less effort over the long haul? Like the tortoise and the hare... if the race is short then the hare wins everytime. Make it longer and the hare burns himself out.
If you want to look at the effects of how the distribution of mass affects the torque on a wheel then check out the claculator for inertia of a thick walled hoop. You'll see how moving the mass closer to the hub affects the MoI.
Hope this helps.