Get Partition Magic and create a D: partition, then use System Commander as your boot manager. The boot manager in PM is ok, but it's more stripped down.
The above will set you back around $80-$100.
Your best bet is to buy another cheap/used hard drive for $40-$60. This would be the ideal way to go since Whistler is so young and ..... who knows. 
I bought 2 removable hard drive cases that I use for WinMe and Win2K. I prefer to isolate my O/S this way because, I simply could not cope with a hard drive crash (or even a serious system crash).
I bought the HD cases on eB*y for $10.ea (new)