I've been playing a bit of freecell lately, and decided i didn't like my 56% win rate and it would take far too long to get it back to 80% or more so i went looking for where they are stored and if they are protected at all.
I found that they are not, this guide is for windows vista, but will likely work on win7 as well (i haven't looked)
Tools:
Hex Editor (this is required)
1) navigate to C:\Users\Administrator\AppData\Local\Microsoft Games\FreeCell\
2) open FreeCellSettings.xml
3) go all the way to the bottom and you should see <./.R.o.o.t.>
4) now scroll up a couple pages until you see <.R.o.o.t.> and then <.S.t.a.t.s.>
5) below that there is <.G.a.m.e.s.P.l.a.y.e.d.>
6) simply modify the number in there to match your games won score (if it's a 3 digit number and your games won is 2, simply hed delete 2 bytes so that there is only space for 2 unicode Chars in there, as we know that those take 2 bytes per character) then modify to suit
7) save and re-open freecell
now you have a better played/won ratio
Also you can use this same method to modify your win streak, loss streak, won last game (so your streak is still running in case you lost the last one)
The next bit to "save" your score, if you ever get yourself in a corner and it pops up with the options "end game" or "return and try again" always choose return and try again, then if you don't want to try to beat it the "honest" way, simply go to your options, and select "Auto Save game on exit" and DE-select "auto load on restart" then close the game, it will save (no loss recorded) then open freecell again and select NO when asked to reload the last game, you will get a new game to play and no loss recorded :)
enjoy
-mazuki