Yes, that’s a much clearer outline, thank you.
Given that you intend to use at least a tablet to run things, then you should have no trouble with putting together something that will meet your requirements (relatively speaking, that is ). If I were working on a project of this sort, the biggest challenge for myself would be in building the robot, so I won’t be able to advise you in that capacity very much, but the rest of it is something that I know a thing or two about, so here’s my 0.02ยข worth:
Unless you’re planning on giving the robot a WiFi connection that allows for continuous contact with the internet during operation, you’ll need conversational software that’s fully self-contained. You have several options here, ranging from something like Kari, which is “virtual Girlfriend” software, has a very shallow learning curve, and already has a built-in female voice (but has it’s share of “negatives”, too), to something like ChatScript, coupled with the talking GUI that I wrote for it, which is very flexible, already integrates TTS and Speech recognition, and allows for using a male or a even a “computer” voice, but has a very steep learning curve. Given that your time-line for this project spans years, there’s no real rush to make a “written in stone” decision, and we can discuss the advantages and disadvantages of each option, if you like.