Do you have a second hard drive? One of those makes formatting a lot less painful.
You can also get a DVD burner for about $NZ35 now, so they're quite cheap.
Also, have a look at <a href="http://support.microsoft.com/default.aspx?scid=kb;en-us;324764">this</a>, it might help.

Having said that, though, I would go with Dr Unne's method anyway, because Windows is crap.