Wireless limited to 15mbps? Do I need new router?

Using D link D524 54G 2.4ghz router
On speedtest, I'm getting
15mbps - wireless
30mbps - wire

On M17x R3 stock wireless adapter (Dell Dw1501 n-adatper)

Do I need new router? new adapter too(dw1501 cant receive 5ghz signal)

hows linksys drt160n sounds? Amazon has for $25 and its dd-wrt

 

You need a router that is capable of 802.11n speeds to exceed 20mbps wireless throughput.
You do not necessarily need to move to 5GHz band. Use inSSIDer to survey surroundings and check if 2.4GHz band is overcrowded as it is or not.

As for the router- if you can stick to 2.4GHz band then a Linksys WRT160N for $25 is a good deal but if you need to move to 5GHz band it's gonna require a different router (and as you've pointed out a new Wi-Fi card)

 

Those speeds are a little low, but not abnormal for wireless g networks. Like downloads said, check the state of the 2.4GHz band and make the choice of a dual band router depending on crowding of the 2.4GHz band. If you need a dual band router, the netgear WNDR3700 and the Linksys E3000 (currently under $100 at newegg due to the release of the E4200) would be good choices.

For the wi-fi card, Intel 6200 obviously.

Again, this only if you need or want to make the switch to 5GHz.

 

This is weird. Speedtest shows 30mpbs download but my torrent wont go over 1.1MBps download using wire

 

Your router is extremely weak it has virtually no RAM and very slow CPU so it's not going to be good with multiple connections.
Another possibility is that your ISP does employ some kind of traffic shaping but my money is on the router- it's ancient and it was designed back when a 5mbps connection was a dream come true.