Is there any way to backup installed programs to DVD. For example when I will install new Ubuntu to install software from the disk and not from the Internet.
yeah you can use aptoncd for it
create one or more CDs or DVDs (you choose the type of media) with all
of the packages you've downloaded via APT-GET or APTITUDE, creating a
removable repository that you can use on other computers. APTonCD will
also allow you to automatically create media with all of your .deb
packages located in one specifier repository, so that you can install
them into your computers without the need for an Internet connection.
This will work only if you didnt clear the apt cache