I've been using Defraggler for close to a year now. Yes, I agree, I prefer it over the built-in defrag utilities because it's a lot more illustrative and shows what it's defragging in real time.
I find I have good luck with a program called "Defraggler". It's free to download and use, but since I didn't make it I won't swear that it works perfectly on every system, just that it works perfectly on my windows xp system.