TCP recive window help required

I got a new broadband connection , which is ADSL and 256kbps line , i had very low speeds , so called the ISP he came home with his laptop which had crapy windows OS , he showed me that the speed was good and it was giving a constant 30kB/s download speed , but here in Ubuntu its only around 12-13 , he said i need to set the TCP window receive and sent values properly , so i did using

sudo sysctl -w net.ipv4.tcp_rmem="4096 65000 187000" net.ipv4.tcp_wmem="4096 65000 187000" net.ipv4.tcp_mem="187000 187000 187000" net.ipv4.tcp_no_metrics_save=1 net.ipv4.tcp_moderate_rcvbuf=1

command , as he said the value should be 65000 , i did that , then applied and restated the n/w , but no use.

And when Transmission was alive ,the condition was more worst , so i did open up few suitable ports
didnt help much , now using Vuze , its bit better , but according to my sped it can download only one and a time , and upload speed is more than the download sometimes .

I m totally fed up , to see higher speeds in windows !!!