You are actually getting low speed in both wired and wireless medium. Which firmware you are using ?
Please try to use latest firmware of your choice.

20mbps or 20MBps ? With 11g wireless router you can not get same speed in wireless and wired medium because usually these are fast ethernet (100Mbps). To get a competitive speed you need to switch to 11n router.

is it the same machine? I mean, is it like a laptop, and you get 3.5MB with it when hardwired, and then when you disconnect it and go wireless, you're getting 1.2 on the same machine?

Or is it a desktop and a laptop getting two different speeds?

Does the machine have the same IP address when it is hardwired as it does when it is wireless? If not, do you have the ports forwarded from the router to the bittorrent software properly?

...or, did I understand correctly from "when downloading with only cable that doesnt go trought the router" that when you're using hardwired mode, you're bypassing the router all together, and it has an external IP address?

It sounds like you could have a port forwarding problem. When going wireless, it's behind a NAT router, and bittorrent is sensitive to NAT unless you do port forwarding. That would affect your speeds. And when you're hardwired, you're not using NAT, so it wouldn't have the same effect. Could this be it?

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You've opened every single port? You might as well just tell the router to put your laptop into the DMZ. BTW, have you tried that? You offer a screenshot of the utorrent. But what I want to know is if the ports are forwarded IN THE ROUTER.

Is QOS enabled on the router? I can't think of anything else you could deliberately do to make the router slow down the traffic.

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