2 dvd+r to 1 dvd+r

[NYguy]

I used 'dvdXcopy' to burn one dvd to 2 dvd+r disc. Now i wanna combine the contents of those 2 disc into one by using 'dvd decrypter' and dvd2one.
or may be combine the two with 'dvd decrypter' and select only some chapter to copy into one dvd disc. Any suggestions.