Guys, please stop feeding the troll. I've reported him - can we leave him for the mods to sort out? There's someone who's actually asking for help.
I am lost. I am not afraid to read, but feel i could read a while before getting my bearings. I am still dazed and confused with the differences, and can't even seem to choose a class or recognize my familiar options.
Since i know it's so different, i'll just try to give some fluff and preference ideas.
In 3.5 i usually multiclass, or multi prc. My favorite themes are; skillmonkey, stand alone, 5th wheel, ultimate disguise, high destiny types. Often rogue, facto, chameleon, or SAD multicasters. I don't even know if those options exist in 4e.
4e has 17 skills, and everyone gains general skill ranks as they level up. Which makes 4e a good system to play skill monkeys in.
In detail, rogues work out of the box - especially the Essentials Thief. 7 trained skills out of the 17 in the game as a default (you can easily get more). The classic PHB rogue only gets 6. Also Bards get a +1 bonus to all skills they are not trained in, can buy a feat to get a further +3 (remember that skill training is only +5), and can take as many multiclass feats (read: small crosstraining rather than actual whole level dips) as they like (other classes can only take multiclass feats to one other class). Also the executioner is worth mentioning - in combat it's slightly weak and it doesn't have quite as many skills as the rogue. (5 is still pretty huge). But instead of daily attack powers it gets poisons which it can either use as blade venom or e.g. put on someone's food. And from 8th level the class really is a master of disguise.
In general, I think you will be more satisfied with the 4e skill monkeys than 3e ones. But the Batman Wizard has gone right out of the window. Spells augment rather than replace skills. And because (other than rituals) you only have a few spells at a time, they diversify characters much more.
Ack! *shudder* That's too big for 4e - I'd try splitting the games in half.
and though some may drop, i see the potential for a more stable game. So far i've not joined. Most have never played 4e, and many never 3e and one only 2e, and a few brand new to dnd. They have all the bases covered, but might need a tank.. . which i'd rather not play.
4e tanks are very very cool. In 3e a tank was a walking sack of hit points trying to get in the way. In 4e, fighters are lethally fast guys who you simply don't dare turn your back on or they
will 



you up. Attack someone else when the fighter has his eye on you and he can cut you in half. And it really doesn't hurt both that 4e characters have a greater ability in skills they aren't trained in, and that climb, jump, and swim are now part of the athletics skill, giving tanks much greater breadth of skills even before you get into utility powers. (It's not that hard to give a 4e fighter the breadth of skills of a 3e rogue - athletics covers three skills, stealth covers the old hide and move silently, perception covers the old spot, search, and listen, thievery the old pick lock, sleight of hand, and disarm traps and with just four trained skills you have the equivalent of an entire rogue's loadout).
Not your archetype - but much more fun than they used to be.
The role i have in mind (though i may not use it) is a fellow from earth circa 1500. He knows of cannon, but could not build one to save his life. He was transported here in his early teens, and doesn't know how. He thinks he might be 'over the ocean' but is fairly certain by now he is on another plane/etc.
If this was 3.5 i would play facto, and keep looking for a way home.
I think you can do the same thing with a 4e bard. And it's difficult not to get seduced by the "Vicious Mockery" at will power. Or even a rogue using better than normal knowledge of anatomy and some interesting tricks.
So i'm lost, and it will probably take a minute to get from lost to satisfied with a build. OTOH, i don't really want to work hard at a new game, and i don't wan't to be so broken the other players don't have fun.
As long as you avoid hybrids and start at low level, very little in 4e is broken. (The cumulative effect of a dozen different minor advantages kicks in in paragon, but there's no one point you can really pinpoint).
A little SAD and broken would be ok. The little reading i did said maybe swordsage/warlord?
Swordmages are a type of tank. They basically hex enemies and then get to punish them if they don't attack the swordmage. Which allows the swordmage to tank by kiting. Warlords are fun - one of my favourite types is the stereotypical drill sergeant on the battlefield, yelling profanity at his allies and telling them that his old grandmother could do better to spur them on.