Never seen any of it. Is this a show where I can watch in release order, or are there prequel movies and flashback episodes and stuff that need to be reordered?
Also, is there a difference depending on where you watch it? Some shows have censored episodes, removed jokes, or of-the-moment "special"episodes. (Like The West Wing’s 9/11 episode)


Release order is fine. I wouldn’t worry about the Angel crossovers, you’re not missing anything critical by not watching it. I’d feel free to skip the first season as well if you’re not feeling it, the show really only kicks into gear in its second season.
There are some Angel crossovers that are literally one episode across two shows. It might be a bit jarring to watch those separately. I believe they only lasted one or two season before buffy moved networks though.