1. If you turn off *Keep iTunes Media folder organised* you can put the files just where you want.
2. Alternatively you could make them into a TV Show where the moives are different "episodes" of one "series".
3. Or you could just stop worrying about the layout of the files and let iTunes worry for you.
In an ideal world iTunes would use the Album field to control the folder name and the Name as the file name. I've just checked but as I'm too often reminded this world is less than ideal...
I'd recommend option 3 but can't help myself from using option 1.
I have a similar question but I am using my IPAD as a sales tool and have covernted many 1 to 2 minute videos through Itunes to download on my IPAD. I would like to create subfolders and file these different folders so I would not have to go through each one to find what I want to run. For intsance one folder would be In-service vids, one folder would be trouble shooting vids, etc.
Any suggestions. Maybe I need to copy them over in a different manner. Like creating a folder with on computer them importing as a folder in Itunes instead of as an individual video.
Did this solve the answer to the OP's question? If so, how?
In #1, if you turn off the auto organization, how then can the OP create a "Harry Potter" folder that will be shown in the "Movies" Library and will contain the 3 different Harry Potter movies (so you click on the Harry Potter folder and then it lets you choose among HP 1-3)?
#2 seems like it would work, but then wouldn't the Harry Potter folder be in the "TV Shows" Library?
#3 doesn't work, which I think was your point.
Well the original question seemed, to me at least, to be focused on the physical layout of the files.
With #1 you can arrange your files & folders any way you like, but the folder structure won't affect what happens in iTunes. iTunes doesn't have a feature to group movie series together. What you can do is adjust the sort fields if necessary so that movies from a series are listed side by side and in the correct order.
With #2 iTunes will arrange the files in a single folder and group them together in the TV Shows section. Whether or not this appeals is a matter of personal taste. I've got all the Pixar short films that have been released in the iTunes Store and rather than have these scattered around the Movies section of my library I treat these as a TV Show.
In #3 I was making the point that, for most purposes, it really doesn't matter where the files are stored on your computer as long as you can access them on demand. Personally I have wasted/enjoyed many hours tweaking the physical layout of my library in ways which have absolutely no effect on the way iTunes displays the library or organizes the content on my devices. See Grouping tracks into albums for my tips on organizing things within the iTunes interface.