Wow.  A couple of those comics that you mention up there... Prez and House of Secrets, off the top of my head... have pretty good tie-ins to my favoritest comic of all time, Sandman.  Yes, I'm a perky-goth(-by-default) girl.  Stereotypes exist for a reason

I'm with nattata... very curious, what's your fave comic?

@godfatherofgreenbay - Frank Miller's treatment of Batman is awesome.  May I recommend Alan Moore's Swamp Thing, if you haven't picked it up already, and Hellraiser (the inspiration for Constantine, the movie with Keanu "Woah" Reeves) which is a spin-off but IMO really good.  V for Vendetta is another good read.  Also, if you don't mind a bit of vulgarity (okay, there's more than "a bit"), Transmetropolitan is another one of my faves.  I was re-reading it during the 2004 elections, and it was a little... unsettling.  Preacher was decent, too, but a tad bizarre.  I've already mentioned Sandman, and there are several spin-offs from that series that are good.  The best is probably Lucifer.  Gaiman's reimagining of the fallen angel is superb, and although he doesn't write Lucifer (the series), the "feel" is definitely carried forward and it works wonderfully.  Books of Magic, another spin-off of Sandman, is also good, but not nearly so much as Lucifer (except for one novel in the Books of Magic series which featured Death... that one was cool).

Most anything from the DC/Vertigo line is top notch.

Sandman was really the first comic/graphic novel I ever read (I use the term "graphic novel" really only to describe a collection of comics, but I understand that many people use it to differentiate between the pulpy, silly stuff of the 40s and 50s and the more adult, sophisticated works from the 80s to today).  Unfortunately, when I picked it up, I had no money and so was at the whim of the local library, which meant I had to read them out of order.  One word of warning is that the first book (graphic novel, collection, whatever) is really slow and doesn't adequately capture the magic or epic-ness of the story.  You get a better flavor of that in the second book.  The great thing about Neil Gaiman, who wrote the entire Sandman epic, is that he also writes absolutely wonderful "regular" novels, like American Gods, and Good Omens (with Terry Pratchett), and even very entertaining and thoughtful childrens books, like Coraline (movie to be released 2/06) and The Graveyard Book (he won a Newbury for this one, and it is apparently already being made into a movie... they just picked up a director.  I just read it a few weeks ago, and even though it's a kids book, I really enjoyed it).  He's definitely my favorite author, in BOTH media (comic and novel).

Regarding Watchmen, unfortunately I read that one after already picking up V for Vendetta, Swamp Thing, and Sandman, so it wasn't quite as "fresh" and "against the grain" for me as it was for those who read it when it first came out, or as part of their first foray into the comic/graphic novel world.  It didn't have the same impact on me as it did on other people, but I'm still looking forward to the movie a LOT!

@godfatherofgreenbay - There's an issue of Swamp Thing in particular that's just incredible.  Basically, he falls in love with a human woman, and they have swampy sex.  It's just not something that I can describe adequately, and it wasn't at all inappropriate (I was reading it at work, that's how "tame" it is), but after reading that issue, I felt like I needed a cigarette!   It was really beautiful.  Despite that, I never finished the series.  I planned to, but my library sucks, and they're kind of getting expensive nowadays.  I've already got enough debt.

Sandman is absolutely amazing, though.  If you haven't done so, put that one at the top of your list.