I have:
CPU: Intel Core i7-860 (Quad core) 2.8 GHz
Mobo: Gigabyte: GA-P55-UD3P P55 1156 pin DDR3
RAM: Patriot Signature 4GB 2 Ghannel Kit DDR3 1333 (for Intel 775 pin, Intel p55, AM3)

The set-up is about 1 year old & my 2TB HD rarely shows defrag at worse than 0.5%, most partitions are 0.0%.
On the whole I consider my computing is slow.
Slow to load, slow to wake up, slow to launch programs, & slow to shut down.

What infuriates me is that only very rarely do I see CPU utilisation higher than 20%, & then it's usually around 37% doing flat out file copying. Also very frequently below10%.
I have a couple of widgets providing this info:
Core Temp reports RAM usage.
CPU Usage shows the utilisation average & with each of 8 "cores".
As I write now I observe the RAM usage at between 40 & 60% while the CPU usage is only 12%.
Simultaneously TaskManager shows 00 CPU usage for all running processes.

Can anyone offer some explanation (I'd be happy to run any recommended benchmark tests) or what I might do to sort this out.
I can remember when my first Pentium II processor seemed just as fast although that rapidly lost speed.

You shouldn't expect more than a small percentage of CPU usage, so that is normal.
Same with RAM, except that 2GB of RAM is pretty normal too.
If you really think that your computer has a problem, it would most likely be virus related.

You extremely large primary drive may be responsible for part of the slow boot / resume.

Win 7 actually misses some big drives on resume if they take too long to spin up. There's a hot fix in place for it.

Have you ever actually taken a stopwatch and timed the boot?

im guessing u have one of those 'green, power efficient' drives...well that wont give u computing experience that a good fast performance drive would...especially, u mentioned the start up time, that depends alot on the drive's performance