Linksys wrt54gs

Hi I bought this router WRT54GS frm Pc world thinking that it could help me increase my download speed but it has competely deverstated me i mean i have followed all the on screen cd guidelines but still i cantconnect to the internet through the router i have to connectto the internet again through my other modem speed touch 510 frm my internet supplier.

Actually the problem i have is about this stage internet configuration type actually which is the best option do i have to select from the drop down menu thereis an option leave the settings as they are or select pppoE which leads me to ask me for my id adress and password but still wen i enter them still there and finish well coz on my screen there comes the mesage that i have sucessfully configured my router but even wen i i restart my computer icant conect through using the router my wep page shows me that the page i requested cant e displayed and that am off line.

Please assist me your help will be of great assistance and at least i wont regreat spending my money for no gain.Actually do i need to trouble shoot i am seriously troubled.

Henry