I think if you don't want to spend money in software made by third parties, with such an old version of Windows your only option is Clonezilla. Ther could be other free apps around that I'm not aware of.
It worked fine with me when we tested it to replace the old Ghost we use at work, fearing it would not work well with Windows 7; as a side note, Ghost (for DOS) did work well, so we still use it (to clone hundreds of machines, including old laptops with win XP, not so old with Windows Vista, current ones with Windows 7).


Of course, there are several other applications for a price.