can a dvd recorder copy from pc to recorders hard drive ?

I have a Sony DVD recorder which can record the video output from my computer's graphics card in the same manner as recording from a SKY box or FreeView box, but it is only recording video signals..

If you want to copy raw data from one hard-drive to another, I'm afraid that doesn't work. Every DVD recorder manufacturer has its own video format within their recorders (most discs can be played on most other recorders/players, once they've been finalised).

Even if you were able to transfer the raw video data, your DVD recorder would not be able to make sense of the data format.. It's one way that the manufacturer can prevent DVD piracy..

So, to summarise;

If you want to record video signals from your PC's graphics card (TV out, HDMI (if your recorder supports it) S-Video, RGB etc.), then YES

If you want to transfer raw video data from one HDD to another, then NO

If the DVD recorder has USB input, you can transfer movies to a USB stick-drive, then to the dvd recorder's hard drive via its USB terminal.

I think the Iomegas hard drive you saw may be a media player with a build-in hdd and have outputs for tv.

No, sorry, not possible. DVD recorder is a closed system, you can't upload or download from it.