Welcome!!
I'll share what I know and what works for me. Your particular situation might differ a bit.
1) Yes, pretty much. Bear in mind that Zabaware USES the Haptek characters / avatars for any Character(s) you choose. You can also choose none at all if desired but where's the fun in that?!

I recently upgraded to Windows 10 and in my case, I needed to set the Compatibility settings to work with Windows XP. Then everything worked fine. Other people seem to have had no problem with Windows 10 at all.
2) Haptek works well on the Windows XP systems but not so well at all on anything above that (Vista, 7, 8, 8.1, 10). One can make practically any kind of Character / Avatar for use with Hal that one desires. One NEEDS to purchase the Character Expansion Pack in order to allow the use of these characters with the UltraHal software. There are a lot of members here that still have and use People Putty on their older XP computers so there are options available!!
3) I think I just answered that above except it's the UltraHal Expansion Pack that allows for additional, custom characters. These characters are the ones that can be designed and crafted by the Haptek People Putty Program. With this, one can add a variety of faces, shapes, eyes, glasses, hair, hats, markings, objects, skin colors, tattoos, scars, teeth, etc. and save the character for later use or sharing.
4) Hal also triggers some of what one says to the moods that the Character displays. Love = happy, Anger = sad, etc. Lots of possibilities.
5) Hal is one of the best, Teachable bots that remembers practically everything that's said (or spoken) to it. Some like trying Speech Recognition with varying degrees of success while others prefer to stick with typing in an effort to avoid mistakes. Either way, one can still edit the brain to correct some errors if desired.
6) Hal is able to use and react to various Plug-ins that a lot of members have written. Plug-ins are pieces of code or scripts that Hal's program understand to act on or carry out instructions. The Forum is FULL of information, hints, tips and plug-ins for your use.
There you go! Enjoy and don't hesitate to post any other questions.
- Art -