Looking to build a new mini PC Is this any good?

So I am looking to build an small ITX form factor PC that will be used for simple browsing and multimedia purposes (under WINDOWS 7 when it's released) and I came up with this:

http://www.newegg.com/Product/Product.aspx?Item=N82E16819116265
Intel Celeron E3200 2.4GHz 65W CPU

http://www.newegg.com/Product/Prod [...] 6835220034
SILVERSTONE 90mm CPU Cooler (used because the case is only 2.95 inches thick)

http://www.newegg.com/Product/Prod [...] 6835100007
Arctic Silver 5 thermal goo

http://www.newegg.com/Product/Prod [...] 6813121381
Intel LGA 775 Intel G41 Mini ITX Motherboard (Will use the built in GPU with shared memory)

http://www.newegg.com/Product/Prod [...] 6813500030
Zotac ION platform with Atom 330 Dual Core CPU

http://www.newegg.com/Product/Prod [...] 6811147134
Rosewill Slim Mini-ITX Computer Case with 150W Power Supply and a 40mm fan

http://www.newegg.com/Product/Product.aspx?Item=N82E16812191086
20 pin PSU to 24 pin MoBo power adapter

http://www.newegg.com/Product/Product.aspx?Item=N82E16822136358
WD Caviar Green 500 GB

http://www.newegg.com/Product/Prod [...] 6822136075
WD Caivar Blue 160 GB

http://www.newegg.com/Product/Prod [...] 6827118017
Sony Slim 8x Drive (doesn't look like the case comes with the 2xm2 screws I need so I'll see if my local hardware shop has any)

http://www.newegg.com/Product/Prod [...] 6812200219
Slim SATA cable

http://www.newegg.com/Product/Prod [...] 6820148212
Crucial Ballistix 4GB dual channel 800mhz memory (4-4-4-12 timing)

http://www.newegg.com/Product/Comb [...] mbo.208025
Windows Vista + Free Upgrade + Windows 7 RC

http://www.newegg.com/Product/Prod [...] 6836121011
Pair of logitec speakers

http://www.newegg.com/Product/Prod [...] 6823109156
Microsoft Mouse and Keyboard

http://www.newegg.com/Product/Prod [...] 6800881303
Easy to use screws

I do have a couple questions,

First off, is it a good idea to run this hardware through a 150W PSU?
I ran http://extreme.outervision.com/psucalculatorlite.jsp PSU calculator using the following:

1 Regular Desktop Motherboard
NO video card (I assume that's what they want if I use the motherboard's built in one)
1 Green SATA
2 Sticks of DDR2
1 DVD/CDRW combo drive
1 80mm fan (even though it's a 40 mm one)
100% TDP for CPU
100% System Load
50% Capacitor again (going to keep this system for a long while)
3 USB devices (won't have more than 3 drawing power at one time)

and the result was 145 W

Edit: Aha! I forgot to put Intel Celeron 3200, that brings the PSU rating to 243 W

Second question, is everything compatible (hardware and fitting winse, I expect it to be somewhat of a tight fit)?

Thanks for replying.

I'm actually just building this. The finished product goes to someone else. That person prefers to have a desktop. I have considered using an ION platform but I wasn't sure if windows would slow down if there were many processes running at once. I don't know very much about ATOM. In your opinion would an atom 330 dual core handle, say, windows 7 with a service pack, Windows Media Player, IE/FireFox, a virus scanner, HP printing systray stuff, adobe acrobat quick reader and a couple of digital camera systray apps and maybe still have a good amount of head room? I've heard mixed opinions of atom and windows 7.

I looked at my OP and re ran the PSU calculator and it turns out that I will probably not be able to use celeron 3200. Rather than changing the case/PSU I think I'll go with an ION motherboard. I would still appreciate an answer to my question about ATOM against Windows 7 though.

I'm considering
http://www.newegg.com/Product/Prod [...] 6813500030
Zotac ION platform

Good idea or not?

More or less at the same time.

I came across http://www.engadget.com/2009/02/11 [...] aunch-det/
and I figure I'll take it at face value and give ATOM/ION a try.