I don't know what formats the iPad can read (I'm not intimately familiar with the iPad) but when you connect it up to Windows, does it show up in "Computer" as a removable device, and can you "open" that device and drop the file there? (there may be a folder tree that you have to explore a bit to find something like \user\media\video or somesuch) I've known that to work on iPods and other mp3/mp4 players in the past.

You *will* need iTunes unless you really want to go the painful way which involves some kind of software that does read and write to the app folders.
Anyway, grab VLC from the app store https://itunes.apple.com/de/app/vlc-for-ios/i … 77962?l=en&mt=8, then itunes to drag and drop the files to VLC (in the apps tab when you view your mini, scroll down to the File Sharing part). Then run VLC on your mini and the files should be there and viewable.
No need to convert the files.

A friend suggested iFunbox, and it's great, and very easy to use, with none of that syncing rubbish, and it's done the job just fine. You still have to install iTunes to use iFunbox, but hopefully I'll never need to use iTunes (or touch another iPad again - my own Android tablet lets you just copy your music/comics/ebooks etc directly to the tablet as though it's another Windows drive, none of that having to use proprietary, bloated first party programs that dictate what you do and how you do it).

Thanks everyone for the answers, and I really recommend iFunbox (http://www.i-funbox.com/) for the job.