I presume you want to make the dvd collection child proof. For that purpose, instead of ripping the video_ts folder, just save an image of the dvd as iso on your hard drive. That will save you the hassle of wondering whether burning the folder back to dvd will work or not, since an iso image can just be burnt to disk and is an exact replica of the original.
From personal experience, i also found that apps used to convert folders to dvd often insert a menu and watermark at the beginning of the dvd which I thoroughly detested. Use an app like nero or poweriso or any image recorder to save the disk image to your hdd.