Memorex Dual Format DVD Recorder won't play video

Just bought a Memorex Dual Format DVD Recorder. It plays music CD's and
runs the software cd that came with it. But when I put a dvd-r or a
dvd-rw in I get an "Drive Not Ready" message. Then my system freezes up
and I get a "Explorer Not Responding" message or something like that.
The disks I'm using were recored on a -R format machine and as far as I
know this Memorex should play -R or +R.
This things going back tomorrow if nobody can help me. I'd like to at
least see what its like to have a DVD player but I ready to give up
already. Hope someone can help.

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