Serious CPU Problem, a bunch of colored wires, and super filthy fan!

[Mind456]

Hello! I'm hoping you can help me with these 3 problems I have with my computer!
[I'm not that computer literate, you know. And there's something wrong with my camera, it can't seem to focus or something.]

1. Won't Start Unless Screwed
Sometimes, my computer won't start up. It freezes at the opening screen or the monitor acts like it can't turn on, or something. However, if I open up the CPU and air it out for a bit, everything works when I plug everything back in.
I'm sick and tired of having to screw open the CPU when I want to turn the computer on! Help please!

As you can see, it's pretty outdated. Bought this XP about 5-6 years ago.

2. Buncha Colored Wires
In front of my computer, there's a couple of usb ports and some audio ports. They don't work, because the wires that connect them to the computer end in a sparkler-like bunch. I have no idea how to plug them in.

Sorry about the blurryness. My camera is like that...

3. Filthy Fan
On my motherboard there's this fan. It is absolutely FILTHY! One light touch and my finger's dust-covered. I need to take it off and clean it, but I have no idea now. Poking a rag between the blades don't help either.

Already tried flipping the white thingys at the end, too..

Help please techies! Other tips welcome!

 

[raybay]

It would be better to tell us the brand and model of the computer, or the motherboard, along with the hard drive installed, and the amount of memory installed.
What security softwware do you use, and what do their scans tell you?
Get yourself a container of canned air designed for cleaning electronics. Do not use a vacuum cleaner or compressed air that is not treated with a chemical. Once the dust is blown out, use a some Q-tips and 90% alcohol or denatured alcohol to clean the fan blades.
What is the output capacity of your power supply?
Any computer that old is at risk because things wear out... You should replace the CPU fan and heatsink, for sure. Your hard drive is old enough to cause worry. If your data is valuable, it is time to replace it. Your signs and symptoms are worrisome.
There are always lots of extra wires in the average computer. They don't cause problems unless they are catching a lot of dust. I would use rubber bands or wire ties to neatly put them out of the way.
First thing, after cleaning, I would do is run a drive fitness test from the website of the manufacturer. Every hard drive maker except Toshiba has one.
Then I would evaluate your memory and increase it if possible.

 

[Mind456]

Info

Here's the info:

So is there no way to connect the wires?

 

[Mind456]

Oh, and how do I do that fitness test thing?

 

[raybay]

The wires are likely there to connect extra devices or hardware, or to connect to other motherboards that are not installed. If your computer needed them connected, it would not work without them.

 

[seanc]

I would suspect the power supply or motherboard is failing.

Power supply is the easiest and cheapest option to replace. It's the big silver box in the top left with lots of wires coming out of it.

Replacing this is quite easy, unplug all the wires that go back into it, take out four screws on the back, screw the new one in and plug all the wires back in.
You should be able to handle that because it's pretty impossible to get the wires in the wrong way round or upside down.

Edit: I've just thought about it, you see all of those capacitors (cylinders with different coloured labels but all have silver tops) that are dotted around the motherboard, are any of them bulging upwards, wonky or have brown stuff coming out the top or bottom?