I wasn't judging you based on Ashlee Simpson alone, but whatever. It's still okay to not like Radiohead; I simply don't enjoy the train of thought employed by some people that you (the general "you," not you specifically) must like certain bands. Fans of Pink Floyd often are often just as guilty of this. I'm not saying anyone here is guilty of that, by the way, but still, it happens.
As for the recent posts involving what band or bands were the best of the 90s, I'd say it would be Outkast...had Stankonia been released in '99 rather than 2000. As it stands, they released one arguably great record (Aquemini), one very good one (ATLiens) and one so-so one (Southernplaya...). As for my pick, I'd lean towards Tindersticks, but that's more for personal reasons, rather than an objective stance at what makes "great" art. However, since I've little concern with looking at this objectively, I'll just say Tindersticks and leave it at that.