This > A box. A box with something else. A basket. A sword. A gun. A vehicle. Practice, practice, practice, practice... and MORE practice. Get 3dsmax or Maya. Practice, practice, practice. Only you can choose what to model. If you haven't modeled yet...model a box? Duh :)
It's good practice to triangulate. However, your low poly wireframe shows some polys triangulated and others not. Are you sure you're triangulating the entire mesh?