The Windows experience is a rating of sorts based on your hardware you have installed in your computer. They really are not critical unless you see a drop during another run of the test. The higher the numbers the more performance your system has based on their ratings . Upgrades are the only way to raise your scores.
lol, I wouldn't worry about the WEI. By setting, are you asking if there is a hack, or are you saying you asking what parts you need to get 7.9?
I have 7.9 on everything except Processor. That's 7.8 and with a email@example.comGHZ. so maybe you need an SR2 motherboard with dual xeon 5680s or something crazy like that to get 7.9. I have 3x580s, a C300 256GB for primary HD to give you an idea of what will give you 7.9.
WIE is not a good measurement of system performance. However the thing that holds most scores back is the hard drive; simply getting a higher-end drive (Caviar Black, Spinpoint, SSD, etc) will raise the score.
^+ very true, if you notice most systems will have 7.5+ in every category and then like a 5.x or so for Hard drive. Good point Shadow. But yes, the WEI is just a number, being happy with your performance is what really matters. Don't worry about some dumb number, or trying to beat someone else.