you have to do it when you are watching a recorded show....
after you put that combination Select->Play->Select->3->0->Select in, it will beep. Once this is done, use the advance button ....somewhere above the 3 i think...and this will be a 30 second skip.
To answer you first question...I LOVE IT, I can't believe I waited this long to order it. I can watch TV whenever I want. Last night for example I started recording a show at nine, waited until about 9:15 to start watching it and I ended up watching a 9-10 show commercial free

It was great!!!