Just got my first DVD recorder for xmas and have a question regarding merging recorded DVD+RW on DVD-R via the PC.

Example.

First DVD+RW recorded several programmes including 'The Office part 1'
which I want to keep.

Second DVD+RW recorded various progs including 'The Office part 2'

Question.
How do I extract both parts of 'The Office' and burn them to DVD-R on my PC.

Sorry if this is the wrong forum, if so please redirect me.
Otherwise can anyone advise on a guide/site to use?

Thanks