I'm an ex Notepad++ devotee!!!! It was hard making the shift to "nowhere land" after knowing exactly how to do things in Npp, but I've gradually discovered that with the right plugins and a few personal scripts which you can easily add via the External Tools plugin, that gedit is the easiest and best transitional editor for hard-core ex- Npp users. I feel your pain ;)
After 4 months of Linux, I'm starting to get a good feel for things, and I'm branching out to GNU emacs because it leaves Npp standing still (really Npp's regex sucks!) I've tried gvim and it seems very good too, but a few things about emacs gel better with me...
gedit with plugins is quite a good choice once you get to realize that this Ubuntu thing is a whole new world... so you need a matching editor... I've got Npp installed in wine for a sense of security, but I virtually never use it anymore, because gedit is basically just as good... and GNU emacs and Gvim are better (but they have a big learning curve) go for gedit.
You may be interested in running Notepad++ in wine
(I was)... so here are some notes I've put together about the bugs I've found using Notepad++ in wine
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