Hi
Well you can do that in Adobe Premiere Elements, you can do pretty much anything including one video running inside another video, and any configuration of title panels and windows.
But I have to admit that the learning curve is probably a lot steeper then DVD Maker.
It does have many standard title and theme setups that are pretty easy to use though, but I always do my own titles, and I haven't really used them, so I can't really say much about them.
But just messing with Windows Movie Maker for a few minutes, it does't seem to have these capabilities.
I couldn't find any way to superimpose one image inside another.
Which gets us back to the original problem.
One thing I would suggest it that you download and install Defraggler.
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I have found in the past when processing large video files (that I'm creating from 3D graphics like Lucy), that defraging the file before creating the video can be the difference between it completing the process or not.
The advantage of Defraggler is that it will let you select files to be defragmented instead of having to do the entire drive every time.
This will take only a few minutes and could lower the overhead enough so that the process will complete without the error.
It may be that the process of creating a 20 minutes movie is just stressing her computer too much.
I don't have those problems any more but I remember when I had to generate video in pieces and then put them back together to get the process to complete, other wise it would just stop and throw an error.
Now with 32 Gigabytes of ram and a quad core 3.6 GHz processor it's not a problem anymore.
Otherwise I don't know what to suggest other then finding software that will do what you want.
Check this out.
This looks like it may do what you want and write to DVD.
Mike