I've always set to start @ 128MB to 4096MB and never had any problems, that way the pagefile, aka swap file, starts out small and doesn't take up a lot of HDD space. But with even a "small" 300GB HDD these days one can just set it @ 4096MB and call it a day...unless you are running out of space.
BTW to the OP, are you sure you are "setting" it correctly? Just entering in the values and clicking on "OK" will not set it...one needs to press the "Set" button next to the values.
W7 uses a little over 500MB of RAM just idling, depending on how much bloatware you have running in the background. The machine I'm using at the moment to post this is my daily browsing machine with only 2GB of RAM and I've not experienced any issues. My video editing rig has 16GB and I have turned off the virtual memory altogether.