Well yes hitachi drives are easy to mod but any drive can be modded but the very newest one wich i think is in progress and every drive that has ever came out that was un moddable was eventually figured out.
Keep in mind too that hitachi is a old xbox that were plagued with problems breaking down and to my knowledge have no hdmi
so if i was not in the knowing about modding or light on cash i would stay away.
The difference between regular and slim is not very much. The slim well obviously is smaller and are a newer more solid design and they are a bit harder to mod then some of the regular ones and some of the newest models you cant mod just yet but everything else is identical.
The difference between black and white xbox is the whites are the old models and am not sure but most of the time have no hdmi output and break down with the 3 red lights.
Kinect you dont need to hack it works with any modded xbox and wether worth it is up to your gaming tastes , i bought it launch day and havent used it since lol I just bought to have but its not my kinda thing , you use your body as a controller and it mimicks your action in kinect compatible games and is alot of good exercise in some cases. Also the big flaw in kinect is you need tons of open space for it to work.Like i have to move my coffee table and tilt my tv and kinect over to the side.
You could enjoy it though but maybe look around you tube for demos of it in action.
when modding you are only modding the dvd drive thats it and the manufacture is your refrence on how to mod it cause each one is different in some ways , some big some small and the hdd doesnt matter at all.
If i was you i would buy depending on what i wanted to spend and if i absolutley needed xbox live. Me personally i would rather have a newer black case regular xbox cause it has hdmi , it doesnt break down and is easy to mod and cheaper to buy used and is same machine. I like the Benq.
if you have bit more money to spend you could buy a pre modded slim or take a risk and buy a new one and hope it can be modded.
Also the jtag modded ones are awsome especially if its the hdmi one. With jtag you can play all your favorite emulators like super nintendo sega and atari ect ect And you can play all the homebrew games and programs
and BEST of all you can get a external hard drive "not some dinky 20gb" with like 800 gb and put all your games on the hard drive instead of discs , there is also other cool stuff but its against the rules to talk about here just google what jtags can do
Also you cant play live on jtag without being banned so that sucks if you need live
You can buy jtags right here on this site in the selling section , they are pretty rare consloes though.
One last thing is keep in mind that eventually new firmware will come and you will have to flash the new firmware if you wanna stay on live or even play new games that are coming out so either you learn yourself or take it in to a pro in your area and pay the $20 to have it reflashed. If your tech savy you can buy those mod kits or that xbox usb pro device or that new lizard flashing device and do it on your own with a tutorial
I think you should wait a couple weeks for the new LT flash firmware to be released "you MUST have for new future games" and buy a pre modded un banned newer black case regular xbox OR preferably buy a brand new regular xbox or and go have it modded in your area its cheap but dont bother till the new firmware comes out or you will be making 2 trips to your modder or be banned right away lol
Anyway hope i helped a bit