Hello Rachel, welcome to the forums. I've moved your post out of that old thread and made a new one for your topic.
If you want to try and fix the existing dvds that you've made from DVDFlick, I would suggest using a commercial tool called VideoReDo TV Suite. There is a fully functioning trial that you can download and use for this purpose, and of course the trial is free to use while it lasts.
VideoReDo has a tool called QuickStream Fix that will usually solve problems with audio/video synchronization. The output will be an mpeg file, but you can take this file and make a dvd using VideoRedo TV Suite.
On rare occasions, I've seen the QuickStream Fix fail. For those, I'd suggest using the Audio Adjustment tool within VideoRedo, and look at the preview while doing so. Adjust the audio until you get it synchronized with the video, then save as a new dvd.
Another way of tackling this whole issue is to try a different tool for making your dvds from your original source files. I prefer a program called AVStoDVD. It is free to download and use.