Computer will not boot to windows.
The light you're referring to is the HDD Activity Lamp.
(HarDDrive)
It blinks green when it's operating, and orange for inactivity, or not operating.
You're getting to the BIOS Post screen, but BIOS is handing over the computer to the Operating System.
(Windows XP is an example of an O/S)
When you press the Power On button;
1) A temporary connection is made from the motherboard to the power supply. A 5 volt circuit is made. This turns the power supply on. (Soft Power On)
2) The BIOS chipset, is the first chipset to receive power. (Chipset is a slang term for IC. Integrated Circuit)
The BIOS program, ( 64MB in size), looks to see what all devices are connected.
(Harddrive, optical drives, mouse, keyboard, etc.)
3) Then BIOS does a Ram Memory count,
4) Turns the Processor on,
5) Then hands the computer over to the Operating System.
It looks like BIOS has recognized your Intel Pentium 4 processor, (2.66GHz frequency rate, 533MHz FSB), but hasn't turned the processor on.
[Let me stop,and explain something real quick.
Where you see -
Intel (r) Pentium (r) 4 cpu 2.66ghz (133x20.0)
The r stands for Registered. Intel and Pentium are registered trademarks of Intel Corporation.
It's a Pentium 4 model.
2.66GigaHertz is the Frequency Rate. Slang term for frequency rate is 'Speed'.
Giga = Approximately 1 Billion
Hertz stands for Cycles per Second.
At maximum capacity, your Pentium 4 processor can operate, at a 2.66 Billion Cycles per Second frequency rate.
133 stands for 133Mhz. 133 MegaHertz.
Mega = Approximately 1 Million
This is the Clock Rate. Intel processors are 'Quad-Pumped', so the FSB is actually 533MHz.
(FSB = Front Side Bus)
The 20.0 is the multiplier.
20 times 133Mhz = 2600 Mhz,
or 2.66GHz ]
Now, why is the processor not turning on?
Suspect the Power Supply.
Not enough power to turn the Processor on.
1.ALL the lights for your computer use less than 1 Watt.
2.EACH fan uses 2 to 3 Watts.
3.A typical processor uses 55 to 125 Watts!
(The Processor hasn't been turned on, so nothing else is receiving power yet)
This is the basic specifications for your processor,
http://en.wikipedia.org/wiki/List_of_Intel_Pentium_4_microprocessors#Prescott_.2890.C2.A0nm.29
Scroll down the left column of the list.
Where you see Pentium 4 505, Pentium 4 505J, and Pentium 4 506. Your processor is one of these three.
Scroll across. You will see 2667 MHz. 2667Mhz is rounded off to 2660 MHz, or 2.66GHz.
You will see 533M/T as you scroll across.
M/T stands for MegaTransfers. A more accurate description of FSB. Front Side Bus.
Scroll further across. You will see 20x. This is the Multiplier. (Look up)
Lastly scroll across a little further. You will see 84W.
This stands for 84 Watts.
Your processor operating at maximum load, uses 84 watts.
Why do I suspect the power supply?
Because it's the number 1 thing to fail in a computer.
Electrolytic Capacitors fail inside, or are failing.
They have Electrolytic Paste inside them.
The paste has developed a gas, (Hydrogen gas), and has popped seals for the capacitor's case.
This results in Electrolytic Paste slowly oozing out of the capacitor, and resulting in the capacitor failing, or has failed.
Electrolytic Capacitors are used as Filters in a computer power supply. They filter the incoming AC electricity from your house, and the outgoing DC electricity made from the power supply.
When capacitors are failing, or have failed, they create a bad power rail.
There are three main power rails in a computer power supply.
1) The 3.3 Volt power rail
2) The 5 Volt power rail
3) The 12 Volt power rail.
With a weak power rail due to failing capacitors, or a bad power rail due to failed capacitors, you do not have enough power to turn the processor on.
Solution?
Use a known, good, compatible power supply for a test. If the power supply is found to be bad, replace it.
Questions?
