For the last couple of years I've played the official Premier League fantasy league - I've played The Sun's one but feel it's not as good. The Premier League's one is still simple to play even though it's slightly more involved and the best thing is you won't be supporting Murdoch or News International by playing it. My girlfriend's brother swears by Yahoo's fantasy league but I had a look and it seemed like far too much work.
http://fantasy.premierleague.com
(By the way - I'm not in any way associated with this league other than as a punter - I'm recommending it because I've enjoyed playing it; not because I work for them!)