yes you're better off just making them into regular VCDs of 2 CDs. Will yield you the best results. As mentioned, you will have no guarantees of it working any other way (unless you do an SVCD which still requires 2 or 3 CDs).
Also if you don't plan on playing it on your standalone DVD player, you can always just make a DivX of it that will fit onto 1 CD (but make the divx from the ripped DVD files, not from another format for best results).
Good luck