I recommend that you use DVD+ or - R (or RW) disks. Saving them on DVDs instead of CDs has two advantages.
First, DVD disks can hold 5 to 12 times more data than CDs. What's good about that is you do not have to reduce the quality of the movies you are trying to keep. Just like the file size of a 7 mega pixel picture is larger than that of a lower quality 1 mega pixel picture, the smaller you make the movies, the worse the quality is gonna be, generally speaking. *** BUT IF the file size of each movie file you have is already small enough to fit into a CD, whether you use a DVD or CD disk will NOT make a difference in the quality of the movie. ***
The second advantage of burning DVDs is that you can POTENTIALLY make them playable on a stand-alone DVD player for your TV set.
If you decide to buy a DVD drive/DVD disks, consider the followings.
If you just wanna save the movies to play on your computer in the future, you can buy DVD disks that are supported by your DVD drive. (There are single layer and double layer DVD disks. Some DVD drives only have single layer writing capability.)
If you wann play those DVDs on a stand-alone DVD player, make sure that DVD disks that you choose are compatible with both the DVD drive on your computer AND the stand-alone DVD player. (DVD + or -, DVD-R or DVD-RW, etc etc.)
In order to make DVDs playable on your stand-alone player, you have to burn MEDIA DVDs (not data DVDs). To burn media DVDs, you also need a special software (such as Nero), and this type of soft may or may not come with a DVD drive your purchase for your computer.
I believe (please check) you cannot play movies in CDs on a stand alone DVD player. However, you can always watch them on your computer.
If the file size of each movie is larger than 700MB or so AND you have got to use CDs, then you have two options. Making it small enough to fit in one CD OR cuting the movie file into pieces and using two or more CDs to accommodate the entire movie.
As I mentioned earlier, reducing the file size is likely to ruin the quality of the image (and audio). If the current movie is in MPEG/MPG or VOB format, changing it to AVI format will minimize the risk of ruining the quality. AVI files are more compressed than MPEG/MPG/VOB. In some cases, you can reduce the file size to 40 to 50% of the original without a noticeable reduction in the quality. For that purpose, you have to install a video converter (soft) in order to convert a file from MPEG/VOB to AVI. Additionally, you will have to install DivX codec (free at www.divX.com) so that your computer can play AVI format files. If the files are already in AVI, you can only make them smaller at the expense of the quality.
The 2nd option is to take the files you have, chop them into pieces and save them on separate disks. This way, you do not have to give up the current qualtiy of the movie. A video converter/editing software will allow you to do the chopping.
HOW TO GO FROM HERE
Alright, you got the concept, I hope.
So, first check how big the video files are.
If the file size of each movie is small eough for a CD, then, don't even think about purchasing a DVD drive and/or burning a DVD disk, unless you want to play those movies on a stand alone DVD player.
If the file sizes are small enough for CDs, and you wanna play them on TV, you have to know whether your DVD player can take CDs (I doubt it.)
If the file sizes exceed the limit for CDs, consider whether you are willing to reduce the qualities. Keep it in mind that the standard DVD movies we can purchase and rent are about 3.5 to 4GB per hour. Reducing it to the size that fits into a CD would make the quality equivalent to videos recorded into a VHS tape.
If the answer is yes, burn a CD as "VCD" (about 10MB/minute) or "SVCD" (20MB/minute) depending on the duration of the movie. Alternatively, you can get a video converter to turn it into an AVI file to minimize the qualtiy reduction before burning a CD.
If the answer is no, you can either 1) get a video converter and chop up the files into pieces smaller than 700MB or so (I don' remember exactly how much a CD can hold.. ) or 2) burn a DVD.