You seem to indicate using files from an existing DVD, these will be Mpeg2 types.
Please place one of the original files in the timeline, right click and select properties, what are they?
Using your keyboard Alt+PrtSc will copy the window details to your clipboard, use an image editor to create an image, a jpeg that you can attach to your post.
If as I suspect you are using Mpeg2 files then you can use these to burn a DVD. The total size of the clips will determine how many will fit to disc.
The bit rate/data rate also determines the size of the files.
As I wrote earlier……..
As a guide
At full quality using 8000kbps will allow for 60 minutes of video.
At 6000kbps good quality will allow for 90 minutes of video
4000kbps will allow for 120 minutes of video.
You indicate that the total duration is 1hr 55min this will need a bit rate/data rate of approx 4000kbps, this is deemed to be VHS quality.
If your files are to big, which it seems they are they will need rendering/converting using a smaller bit rate. You indicate using the Optimiser to do this, that’s ok the total size of your Mpeg2 files should be lower than 4.3Gb.
You can convert before burning the disc or allow the Burner Module to convert them.
1 / Start a new Project—nothing in the timeline
2 / Share Create Disc—opens the burner module
3 / Add Media, icon top left—Add video files.
4 / the duration bar should/will remain in the green, Then skip the next parts 5 to 8 and go to part 9
If its showing yellow/red
5 / Click the Project Settings Cogwheel, opens the Project Settings
6 / Click Change Mpeg Settings-Customise
Compression tab, reduce the Data rate to 4000kbps (assuming you have 2 hours of video)
7/ If the bar still remains Red, again Click the Project Settings Cogwheel, opens the Project Settings—deselect Do Not Convert Compliant Mpeg files
8 / repeat part 6 till you have all green.
9 / Next, from the gallery choose a thumbnail type menu
10 / On the last page choose to Create a Disc Image or create a DVD Folder—Deselect Create Disc. Saves you making a coaster.
This will create an Iso file saved to the hard drive, if this is successful then the process of burning is working ok.
You can play the ISO using VLC Media Player.
Earlier versions of VS and X5 provide means of burning the ISO to disc
Read some of my quick guides to Mpeg and burning a disc.
Canuck reference to 400 should read "4000 to fit a DVD"