There is absolutely no way you can watch another programme while you are recording. You can watch a recorded title or a DVD, but no TV channels. To do it, it should have a twin decoder inside that simply is not there. One could argue that, having an analogue and a digital tuner it should be possible at least to see channel from those tuner, but also this is not possible and in any case it make sense no more because we are going all digital.

Of course you can still watch another program on the TV if the TV set has its own digital tuner (internal or external).