Dust buildup in lap tops is very common, when it gets bad you have to open the machine and physical clean it. Your fan is 3 years old, I would replace it while inside. You could install a new SSD while doing the fan. Then a clean install of W7 and you'll be much faster.
I used to get cooling errors because of build up so i used a dust blower at the fan and after that, i got no more errors.
Another aspect of her speed advantage could be her wireless speed. Some lappys have really poor WiFi performance. Look to find a ssd with 256gb of capacity or larger if needed and affordable. Then I used my stock spinner in an external usb powered enclosure, but then I use 64gb SD card in mine for data back up and more portable performance. Don't discount the ssd as it will also enhance battery run time as well as noise, vibration and heat!
Not completely correct, It depends on who make it and the overall quality, you will get some really cheap ones, and some quite expensive ones, I have tried one before and i didn't notice too much of a difference, maybe 5-8 degrees but that 5-8 degrees can be a lot if the temps are really high, also the one i used wasn't cheap but it was expensive either, somewhat mid range, it was easy to use and done the job i needed it to.
I will most definitely consider replacing my fan and getting an ssd im just really worried about opening it and breaking it
To replace the disk, you only have to open the disk bay. That's easy. The fan is another story. You have to watch the wires that go to the screen. Note that a SSD produces a lot less heat than a spinning disk - in fact it produces no heat at all.
OP's RAM is also very slow, it's not remotely close to being a good laptop in 2014.
For replacing the hard drive with SSD I would look at this:
SSD - Install and Transfer the Operating System
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