Are you sure you want to reset EVERYTHING? I started SparkPeople in 2007 and then stumbled off track for a couple of years. I found it interesting to read my old blog entries and use them to motivate myself.
If you really want to reset everything you should probably ask for help from the technical experts. One of the things I've learned about "starting over" is it's better to just jump in where you are. Good luck with your current attempt! The only way to fail is to stop trying!