There is no "best" when it comes to editors. Everyone has their preferences. The best thing for you to do is try several out and decide which is best for you. Since you mentioned Notepad++ I'm assuming you're using Windows.
Conclusion : For those who are having same type of query .
1. Notepad++ seems to be a great tool . Moreover it seems that , much help can be found regarding Notepad++.
2. Wikipedia gives a list of many tools available, you can see that too.
3. Notepad++ offers many plugins that could help you in HTML editing and beautification purpose.
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