It's probably most definitely that you're not used to it in this order. Also, I'm not sure you've seen all the extra footage before in any fashion, but its inclusion unquestioningly alters the way you'll perceive the films.

As for the subtitles/English matter, that was a concession Coppola made to NBC in the editing process. One has to remember that this was broadcast in 1977; television audiences were less tolerant for foreign-language productions back then than they are now. It's somewhat different than going into a movie theater, when the editing of Part II was such that there's a greater balance between English and Italian. In the TV version, there's a good hour and twenty minutes that are almost exclusively in Italian with subtitles. We'd sit for that, but who else would? Whatever could be done to offset that was evidently considered necessary then; that, and editing the violence to conform to television broadcast standards. And evidently Coppola found it a small price to pay for being able to include all the extra footage he shot - and, more importantly, being paid for the broadcast rights and using that money to continue financing the filming of Apocalypse Now.

Previous video releases (The Complete Epic, which wasn't so complete, or the Trilogy) indicate that, for the most part, the original scenes are left untouched, violence and language and all, wherever possible and the additional material added in to supplement that, and should they ever go to DVD with it I have no reason to believe they won't do exactly as you would want.

It's now nearly three hours in, and by now you should have a better picture of the effect the reediting has on the first film. Please keep an open mind; in the long run, I too took up Turnbull's view that this is the best way for me to enjoy the films. With time, you may feel the same. I hope you do.