Sony AW-Q170A-B2 BLACK 18X DOUBLE & DUAL LAYER DVD+/-RW (White box) Burner "dvds show white" Questions

...do detects the dvd but shows 0 bytes of data . I am facing this problem since 4 months. Only sony DVDs are opening n playing on it, for other brands like moser bear it shows sucessfilly burned on ...

Can I play store bought dvds on my new memorex slim external cd/dvd writer? The box says yes but when I install, it just shows the movie name and won't do anything If it is just a writer then no but I