Richard, if I were you, before spending any money on DVDs, I'd look at some vids on youtube -- maybe some people here can recommend them. My reason for suggesting this is not because you may be able to get a freebie on youtube (which is controversial, and for good reason), but just to find out if video learning is really for you. Watch some vids first, see if the medium even works for you as a mode of instruction before you spend money on it.
I saw some Yoshinkan Aikido clips that were really cool.
The structure was something that drew my attention and which I liked.
well the above clip is in Japanese, but there is an English version... this is just an example, anyway.