OpenBSD is absolutely fine for browser, mail and pictures. Once you install gnome, the GUI will generally be the same as most other gnome desktops.
Flash and NTFS are sticking points. Neither work particularly well. I've had variable experiences with VLC for video - it lost sync on earlier releases of OpenBSD and VLC but may have improved. Really, the easiest way is just to try it out! You could always dual boot if not sure. Peter
