replacement parts and upgrades

I have a problem with my Insppiron 530s. I'm not as well versed in IT, so I'm a bit lost in repairing this computer. I need some assistance doing it.

I got this Inspiron 530s years ago and it's fairly old. The first problem I'm having is the heatsink is noisy. I tried to clean the dust, but it didn't help. The fan is worn out. My CPU cooler is potentially broken, but I'd rather change the whole thing.

I also took the power supply apart, too. I'd rather change it out to be sure I don't have a unsafe power supply. Any ideas on a good power supply?

I need to find out what CPU coolers are compatible with this computer and ones that will fit my machine. I'm also curious what this paste you need is, too. I need to know which way the fans need to go, too. I'm not completely sure which way they go.

I also need to know where I can get these parts too.

I'd also like to add a video card too. I need some suggestions on what to buy and how to install one. My TV doesn't use VGA. Adapters don't work either.

Please help.