I know this game is all about unlocking items and files (and such) so my question is this:
Like most gamers I didn't start out on easy, and i'm almost finished first player on normal and 2 players on hard. I was wondering; if I beat the game on normal does it automatically unlock items from both easy and normal or do I have to play through the easy mode again to unlock items given on the end of the easy campaign (I'm assuming you will get something for beating the game on different difficulty)?

You unlock the items by finding them. I don't think you get anything for just beating the game.

Pretty sure it's save file is different too... so yeah you can unlock 100% on any difficulty.

But only get the bonus on hard. (Infinite Ammo for all guns.  Which is lame anyway)

Ok, yes I know the files are to be found but you can also collect items and seeing as though I'm missing a huge bunch of those I thought you would get some when you beat the game.
So you do get bonus stuff when you beat the game? (infinite ammo is indeed pretty lame!)

You unlock a special mini-mode, and if you do well enough on higher difficulties they show you some items from previous games...

Yeah, there's not a whole lot.

Been a while since I've played, but I remember the memento items being tied to getting A's and S's on each stage. Think there's a different one for both Hard and Normal. Also why the diss on infinite ammo? Get a friend, both pick rocket launchers and you can play the game in Michael Bay mode.

Ha ha, Michael Bay mode. That's pretty good.

I don't mind the collecting of items.  RE:UC is a pretty decent game that can be played and replayed easily.  Finding the extra crap makes for good bonuses.  I have found very little of the bonus stuff (haven't played it in a bit), but have all the stages unlocked.

Yeah the game is great fun! Better then I expected. Only the framerate really suffers in some places and there are area's that were given more attention by the developers then others.
All by all I'm content, I will be replaying it alot to get the bonus stuff (most levels I have rank B so that's why I probably have so few items!)
Thanks for the help!

You need to get A and S Rankings on normal and hard to unlock everything. Infinite ammo is cool. Shoot everything with the MRL. :)