Switching to Firefox Browser?

Things that give me a reason to use Firefox(by priority):
1- Tabbed Browsing
2- Built-in Popup Blocking
3- Google Search supported
4- Bookmarks(favorites) Manager
5- Searching through bookmarks by Bookmarks Manager
6- Download Manager
7- Password Manager

Things That give me a reason to switch back to IE:
1- Some websites are not displayed as their are supposed to be
2- Bookmarks(Favorites) are saved on a different location and still looking for that location!!
3- Google Toolbar not supported
4- Some components are not supported natively and need plug-in downloads