I use bada SDK 1.2 and there is no HTML/JS editor.
What project do you recommend to add in Help->Install New Software?
I have tried 2 projects on sf.net(add jars to plugins) but they didn't work.
No HTML or JS editor? If youinstall the WTP from the standard Eclipse update site for your version you should have a (basic) one. Just check in the context menu of a file if there other options under Open with. If there is you can set the editor association in the preferences.
A visual HTML editor ships with the JBoss tools. Despite its name it contains tools that can be used and installed without using JBoss.