For the running out of space option- perhaps it's worth while, if you have a good internet connection, to investigate an online backup solution. There's a few mentioned here.
I'd be interested to know if anybody has experience of any of these.
They do work on wifi and they have been around for a while.
You can get 1TB from Dick Smith for around $110. I don't know, but I suspect you may need more than that if you are going to keep a lot of movies.
Talk to your local electronics retailer.