I would recommend Komodo Edit by ActiveState. It meets all of your requirements of,
- Having Auto-complete & Calltips support for the above lanuages
- Having Projects support
- Compatible with Windows 7
Along with those features, it also has,
- Multi-Language Editor
- Track Changes
- Markdown Viewer
- Kopy.io Integration
- Multiple Selections
- Skins & Icon Sets
- Uses the backbone of Komodo IDE
Komodo Edit is a fast, smart, free and open-source code editor. Switching your trusty code editor is hard, but give Komodo Edit (or its big brother Small Komodo IDE iconKomodo IDE) a try: it'll be worth your while.
Windows, Mac, Linux? Yes.
What else? Fast open (no more slow poking around for files); remote file editing; Vi keybindings (good ones); and a toolbox with shell command integration, macros and code snippets... all wrapped around a tricked-out editor and an extension mechanism the same as Firefox's.