Opposite View
Although this thread is about Macrium it is useful to cover other areas that make imaging easier. Data doesn't really need imaging but an OS and programs do so it makes sense to separate them as much as possible.
I have the opposite opinion.
I am only concerned about my personal data.
Reinstalling all of my operating systems would take about an hour (LM14 - 13 minutes, W7 - 19 minutes, XP - 30 minutes), updating them would take a couple of hours and reinstalling the Windows 7 & XP programs would take about a day.
Trying to recreate and/or download >2TB of personal files would be impossible.
I've accumulated a lot of random stuff during the past 10 years.
For example, my TAFE handouts and exercises would be very difficult to replace.
That said, restoring an image is much quicker than reinstalling everything.
I create images (OS and data) every month before the Patch Tuesday updates.
I also create OS images, before I install programs that I'm not sure will perform the operations I require/expect.
I replaced Ubuntu 10 with Linux Mint 14 (on Monday) so I created new backup images of my primary HDD partitions yesterday.
Speaking of separating everything (OS/Apps and data), I'm curious to find out how whs and lehnerus2000 maintain their systems below 30GB (22GB in lehner's case).
I've been able to streamline my OS drive down to a current size of 33.25 GB. Are the two of you installing some programs on another drive or partition? Is that possible? Are there any general guidelines to follow if doing this?
I attached a snip of some (not all) programs that are currently installed on my C: drive that I might consider moving if this is possible/beneficial.
My W7 partition = ~22GB/40GB
I don't use Hibernation, so I have disabled the hiberfil.sys file (saving ~8GB).
My Page File has it's own partition (on a separate HDD).
I don't have any games installed on my physical machine.
I only have old games which are installed in an XP VM.

Most program installers allow you to specify a path, where the program will be installed (there are some exceptions, like Flash).
I never experienced any problems when I installed my programs on a separate partition.
IMO, if you have mainly XP programs you are probably better off using a separate partition.
When I reconfigured my system (last September) I decided to stop using a separate partition for my programs and I have experienced quite a few annoyances as a result.
I use a few programs that try to write ini files back to their install directories, which Windows 7 won't allow.
Moving programs is generally a PITA and can cause problems.
If you want to shift them, you should uninstall them and then reinstall them in the new location.
Some programs will just automatically install themselves to "C:\" in any case.