Which one do I buy......soundz cliched......I Know :)

[thefox]

I already own a Canon A40 (excellent camera) but as I have outgrown it, I am now looking forward to buy another one with some advanced features. I have the following in mind. Any inputs about the actual picture and video quality would be of gr8 help.

1. Olympus 5060WZ
2. Olympus 5050Z.
3. Pentax Optio 555.
4. Canon PowerShot S1 IS.

What I have in mind is:
1. Very good to excellent photo quality (read low noise, purple fringing and red-eye) in all/most conditions.
2. Good to very good VGA quality movie mode (should preferably record movies till memory lasts & at 30 fps). This is very important as I want to record footage of my kid and I dont want to buy a camcorder for the same.
3. Minimum possible shutter lag to capture action or spontaneous moments.
4. Ideal price should be around $450

Though I am aware that each one of the cameras listed above have some limitations with regards to the features that I have mentioned in my wishlist, I would still like to know which of them is the closest to what I have in mind.

If other cameras(old, new or recently announced) apart from the ones listed above fit the bill then pls do mention the same.

Thanks in advance