YJ,
If you are talking about at idle, not doing anything, I would say the CPU utilizations should typically bounce between 0-10% with occasional spikes to 20% or so, depending on what you have running on your system, within your browsers, etc. I have 4 windows open with aprox 20 tabs at most time, and also have Outlook and Outlook express that poll for new messages on a regular basis.
If you are referring to sitting idle, 14-30 continual seems a bit high, but again, I don't know what you have running on your system.
I am on a 32-bit system right now, which will only recognize and utilize a bit over 3 Gig of RAM, and have aprox 2.2GB available at idle. When I'm playing, my available RAM drops to aprox 1.8GB, and page file usage increases very slightly, which is correct, as it SHOULD write to RAM for faster results. Generally the page file is only used when memory is maxed out, or close.
Did your free RAM numbers come from the 'physical memory' box (Shows in Kb), or were you reading the PF Usage that shows the results in GB?
Processor usage for me jumps to 40-70% when playing, which is where the majority of most lags probably occur for most people. While the processor isn't maxed out, it is a much higher and much more consistent load during game play than what it sees during most typical daily tasks. This, to me, is a big part of successful gaming.
Having the newest and fanciest processor will do you no good if the communication channels to and from it can't keep up. Motherboard Bus types, sizes and speeds are the critical link here, and unfortunately are not adjustable, short of replacing a motherboard. What you buy is what you get, and I'm guessing that the majority of users have very little knowledge of this when making a purchase. Off the shelf store bought computers typically don't even have these numbers advertised on them, and most people don't know to even question this.
Newer computers are getting better at addressing this, but there is still a lot of room for improvement. Part of selling these systems retail is keeping costs low, and the easiest way to do this is to trim costs on motherboards, memory, and hard drive. CPU's are a selling point and normally not an issue. But believe you me, you can put the exact same CPU in 4 different motherboard and the results you get will be quite different.