How to make a villain universally hated?
Make it obvious that they are wrong.
And then it make it obvious that, in the text, they are right.
I'm sure that I have to explain that more... so here goes.
It's fairly common now for people to look back on the old days of the southern white bigots and the whole lynching business and say 'omg, those people were evil.' Whether you want to debate about the various moral questions inherent in a discussion of different ethical and societal rules is beside the point, we, as a society, view those actions as morally reprehensible. Now, consider it this way, did those people consider it morally reprehensible? No. That's what makes them well-motivated, they believe they are doing the right thing, even good. This should be the staple of all good villains (IE: they aren't disney villains, they WANT something, BELIEVE something, and will DO something to acquire/gain it, all the while thinking they are RIGHT and GOOD and never being card carrying villains.) But this isn't the end to it. If this was, there'd be nothing terrible horrible about this series of events. You see, back in the day, not only did the people doing the lynching think they were right, SO DID AN OVERWHELMING PORTION OF EVERYONE ELSE. So, in their time, they were not villains, they were even likely called heroes be a lot of people. In ours, though? Villains. Compounded by the fact that their people didn't think of them that way.
Take this to a story and you've got a truly hatable (and as close to universal as I can even imagine) villain. Someone who does things that we believe are terrible, and not only thinks they are right, not only gets away with it, but is rewarded for it! Someone who is a villain by trying to be a hero.
In short: worst villain ever is the society backing any 'evil thing.' Which is every society, in some way, shape, or form. So yeah.
Past this, though, you aren't going to find anything even remotely 'universal' in hating villains. in my personal taste/experience/whathaveyou. I vastly enjoy a strategic, genius, batman/xanatos gambit chessmaster villain who sets up a giant string of events to get what s/he wants. If they want to blow up the world, or take over the world, or whatever, and do so by less than desirable means, I find them amazing. Someone who is willing and able to manipulate and destroy the hell out of anyone/thing standing between them and their goal amuses me greatly. (It is probably a form of envy, I think). On the flip side, I am a very parental person. Harming a child (not necessarily killing, as that generally either alerts me to 'this sucks' because of shock value or 'they really pushed it to the edge, AWESOME' response. Neither of which are bad things) is a very quick way of getting on my 'evil b*****d I wish you a fate worse than death' list. Especially if the audience is supposed to have gotten even slightly attached to the child (and by audience, I mean me.)
To give examples: Iago (shakespare, not alladin, thank you)? Awesome.
Anakin Skywalker: Pretty much unforgivable. I don't care what the movies try and make you feel about when it comes to his redemption at his sons hands and s**t: HE SLAUGHTERED DOZENS OF KIDS FOR NO ******** REASON AT ALL. There's no redemption for him in my book.