Windows 7 - RAM staying tied up and slow performance

Can someone please tell me firstly the difference between "standby" RAM and "free" RAM and secondly a way to FORCE the computer to give up the "standby" RAM once it's stopped using it.

I'm using lightroom to output about 600 .jpg files at about 100k each, it runs really fast for a bit and then slows down.

i was watching the RESMON and i can see that at times it runs completely out of "free" RAM and has about 6GB of "Standby" RAM available.

see first pic below with 13mb free

Even if i close lightroom and then reopen it it doesn't give back this "standby" RAM.
If i run lightroom on only about 100 files it runs a lot quicker (gut feeling no imperical data) and then if I reset the PC I feel like it holds that speed.

I'm hoping that someone can tell me some way to once I close lightroom i can get back all the RAM that has been grabbed by "standby" and change it back to "free"
my last pic is of the RESMON when lightroom is idle and i'm typing in notepad

see pic with 250mb free

I just want my programs to run fast!!! :-/

p.s sorry i put this in the wrong place, can someone move it maybe????

Your RAM is fine. You have plenty of RAM available. The slow down is else where. The value you need to watch is "Available" this determines how much RAM is available to applications. As you can see in your screen shots, you have a lot to spare!

Standby RAM is the part where Windows pre-loads data that it expects will be needed soon. What's in there depends on what applications you are currently running and what applications you are usually running. If an app requires RAM, windows will release it immediately without any user intervention. In the Windows 7 memory management setup, free RAM is wasted RAM.

The important figure is AVAILABLE RAM, of which you have plenty.

Thanks guys, that makes things a little better!

I've had it use over 6 Gb of RAM before so I'm glad i've got all that available.

Thanks for your help