your router is in Chinese?...there's a chance that could be the source of your problems, since the Chinese government likes to hide things in web hardware intended for their own market, I would strongly recommend replacing that, not because its Chinese made(most routers are) but because its intended for the Chinese market.
if you're feeling brave, and willing to risk bricking your router, you can try and drop an open-source(english) firmware on it
DMZing is the nuclear option you'd choose if port forwarding doesn't work, its roughly equivalent to forwarding all 65536 ports, its a massive security risk, but it does have some potential to help a bit. Since there are very few attacks that target game consoles(due to lack of data stored on them) I won't tell you not to. But any PC player should be warned that, without incredibly strong PC based security software, DMZing a PC is asking for trouble.
chomama actually mentioned the best lag fix for PS3, drop a solid state hard drive on the machine. by modern standards the PS3's harddrive is impossibly slow, and it doesn't have the RAM to back it up
you can try to use this guide
and hope the general placement of controls in the english version of TPlink's firmware is the same in the Chinese version(this is a strong but not certain chance, software developers are lazy) Edited, Oct 5th 2013 10:33am by sscearcev