When I use NeroVision Express 3 SE, it turns a 4.5GB file into 10+GB

I am trying to backup my 1st season of Nip/Tuck and there are 13 episodes. I used DVD Shrink to re-author so I could fit 6 episodes on a disc around 70% quality. When it was done the Video_TS folder was 4.5GB…

When I use NeroVision Express 3 SE (So I can make menues for the DVD, since there are 6 videos on the DVD) it says the file is 10GB and that I need to take stuff off. The crappy thing with this is I can only fit 1-2 videos on per disc (I don’t want to make 6 discs for my backup).

When I use NeroExpress I use the exact same Video_TS folder and drag and drop it into the NeroExpress menu and it says it’s 4.5GB.

Is there something that NeroVision Express 3 SE does that almost doubles the video sizes. If so is there any way to create menues and keep the folder size small?