No distros can write to NTFS...that's something nobody's been able to figure out how to do reliably yet. However, all distros can read NTFS.
As for gui, fluxbox is a window manager. KDE and Gnome are desktop environments. A desktop environment consists of a window manager and some other utilities like a clipboard manager, usually some form of inter-process communication so that apps are integrated with each other, and a whole lot of other things. Desktop managers tend to be fairly large, but full of features. Window managers are lightweight and minimalistic. Gnome is a desktop environment that I would highly recommend. It uses Metacity as a window manager by default so you don't really have to worry about installing anything besides Gnome.
As for distros, yes RPM-based distros have come a long way. RPM distros can now use apt (http://apt4rpm.sf.net/ ), which is the be-all-and-end-all of package management. They can also use Yum, which is more or less the equivalent. Still, if you're looking to avoid RPM-based distros, and still looking for something that's newbie-friendly, I'd recommend trying either Progeny or Libranet. Both of these are based on Debian, and I know that Progeny definitely offers a version of its software for free. The only catch is that the software is out of date, so upon completion of installation, it's probably a good idea to run "apt-get dist-upgrade" to bring your installed software up to speed (if you want really modern ultra-cool software, change all occurances of "stable" to "unstable" in /etc/apt/sources.list...this will get you the latest software, and it usually has very few bugs).