I read that a 15-watt soldering iron is recommended when working with PS2s.
Rosin Core Solder should do the job with no problem. Flux is also recommended to help make contact with solder much easier. Some tinner could help with solder and it's sticking to the iron too. All these you can get from Radio Shack.
I also have a 30-watt soldering iron from Radio Shack and the tip on those are too big for contacts on the PS2.
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