Apologies for this basic question. Booting up takes an eternity so I think I need to replace the C drive then install everything on the new drive. But I'm not sure about the OS (Win 7). Do I just uninstall the programs, take the old drive out, replace it, then use the installation disk to load in the OS? What happens with activation of the OS on the new drive?

When I did this I simply powered down the machine, removed the old C drive (completely intact), and installed the new one. The reason I did this was in case if the new one glitched (I was installing an SSD), I could simply reverse the procedure and get my machine back. Installing the same OS on another drive did not cause me any issues, I simply built the machine up from scratch at that point.

Great. Thanks for the response.

My Windows 7 machine takes several minutes to boot from a fast mechanical drive. You can shorten that time considerably using an SSD. Booting tends to slow down over time because you add more and more programs that want to load into memory, not because the drive fills up or wears out.
 
Before you swap out a drive because boot is slow, it might be wise to figure out if the drive is the root of the problem. It is unlikely that a drive that is seriously impaired, (except by an improbably degree of fragmentation), would continue to boot at all for long. You can run drive diagnostics from within windows or from utilities available from the drive manufacturer that will give you a good idea of how well your drive is working.
 
If the slow boot is due to some problems with software installation (multiple retries to load drivers etc. until timeout) just reinstalling everything from scratch to the same drive may speed up booting. On the other hand, if that is the problem imaging the old drive onto the new drive with drive imaging software may copy the old problem to the new drive.

slartabartfast
My Windows 7 machine takes several minutes to boot from a fast mechanical drive. You can shorten that time considerably using an SSD. Booting tends to slow down over time because you add more and more programs that want to load into memory, not because the drive fills up or wears out.
 
Before you swap out a drive because boot is slow, it might be wise to figure out if the drive is the root of the problem. It is unlikely that a drive that is seriously impaired, (except by an improbably degree of fragmentation), would continue to boot at all for long. You can run drive diagnostics from within windows or from utilities available from the drive manufacturer that will give you a good idea of how well your drive is working.
 
If the slow boot is due to some problems with software installation (multiple retries to load drivers etc. until timeout) just reinstalling everything from scratch to the same drive may speed up booting. On the other hand, if that is the problem imaging the old drive onto the new drive with drive imaging software may copy the old problem to the new drive.

Thanks, slartbartfast. I'll do some more checking before taking the plunge.

Go SSD for boot drive.  No if's and's or but's if you r serious...
I assume you have a second/third drive for samples/songs... if not, you should... drives are dirt cheap!
If you have time, do a clean install...new SSD, format, install win7 then X3... 
you'll be set.
 
I just did a big rebuild... cloned drive to new SSD...as I have a huge pile of stuff to redo/reauthorize if I did a clean install...and was eager to start playing again after 4+ months of no DAW... I wish I had just bit the bullet and clean installed everything as I'm probably going to do this down the road...housekeeping hasn't been what it should have been... 
 
btw, use old drive for backup...wipe it and check it (lots of utilities for this) or just get an external... they're dirt cheap 

Cheers, Vastman. I appreciate your input.
 
I've actually got an SSD as the boot drive on another system I built last year - my first build. Yes, it is certainly a lot quicker than the other system which has the slow drive. I'm just considering all the options right now, including cost. In any case, I'm pretty sure that a clean install is the way to go.