cpu usage

[nork]

I am running win 7 ultimate 64 bit with 4 gb ram, newer Asus mobo with intel quadcore i7 860. I have that sidebar gadget working on my desktop and i am just wondering if the info it reports on the memory is good or bad. The cup usage is always pretty low.
When i boot up the memory section shows 30%. When i turn off things like the The Weather Network and a few other small progs then the memory section goes down to 25%. right now its at 31%. That is with wordperfect open, a notepad file opened, and, of course, i am using the internet.
Are these numbers indicative of a system running correctly? MY concern is that i wonder if i am using too much of my ram and its slowing me down? I am happy with the pc and i feel its running fine most of the time but sometimes there is a lag when i have several progs open and when i move from one to the other the system lags a bit. but that is likely another topic. So mainly i am asking about those 25% and 31% numbers. Are they what is to be expected? Does this mean i should add more ram?
Thank you for reading this and thanks for any help you might give me.

 

[logicearth]

It is fine....You have a butt load of RAM you want it to be used. Using more RAM improves performance it does not hamper it...Well until you start using more then you have, but Windows already handles that. The lag you speak of could be I/O which is the absolute slowest aspect of any PC.

 

[nork]

Thanks for the reply. I should have pointed out that the other day the ram usage was up to 48% and i was experiencing a very long lag. Maybe it was a co-incidence and maybe something was running in the background i didnt know about. I know that hasnt happened again.
thanks again