Hi there,
Most pre recorded DVDs come with subtitles, it should state on the back if it does alongside which languages the DVD supports and the aspect ratio / surround sound info.
As for CDs I assume you mean DVDs ?
If not then there are only two basic types, CDr which will allow you to record audio, computer data (word processor files etc), pictures onto the disc. You can add more data at a lter dat if you want (called a multi session disc) Once the disc is full it cannot be wiped over and re-used. These discs can be used for video (Video CD) but the quality and storage capacity isn't great. If you want to record video on disc you should look at DVD, much better quality and compatibility.
Then there is CDRW (rewriteable) which will do the same but you can wipe over the information and re-use the disc again. Look here for more info
http://en.wikipedia.org/wiki/CD-R
With DVDs it's a little more complex, as there are 3 different formats DVD ram, DVD-R (and -RW) , and DVD+R (and +RW). Only buy the type of discs suitable for your recorder as the 3 different types aren't usually compatible. There is a lot more information on this website if you'd like to take a look.
http://en.wikipedia.org/wiki/Dvd-r
http://en.wikipedia.org/wiki/DVD%2BR
http://en.wikipedia.org/wiki/Dvd_ram