DVD To AVI

I’m really new to this, but was wondering how to copy a dvd with a series on it ie: tv series. I would like to copy each episode so i can combine the multiple season dvd’s on to one cd, plus be able to store the large series on my computer via avi in sequencial order. I have tried to copy the first dvd using DVD Cloner 3 to my computer, but when I open the folder it has 4 vob files (each file contains .99 gb) 1 vob file containing 152 mb, 2 ifo files (1 with 6 kb and 1 with 92 kb) and 2 bup files (1 with 6 kb and 1 with 92 kb). I’m not sure what each file means so any info would be greatly appreciated. FYI, I have a DVD to AVI program, a AVI/MPEG/RM/WMV joiner and DVD Santa.