Wireless LAN Speed - Getting Faster?

[#1]

I have been on the 40Mb FTTC service since quite early on, and today have gone live on the 80Mb FTTC service.
Wired, it works superb and I do get almost full speed up and down (I am very close to the cabinet), but over wireless I struggle to get above 45Mb.
My router is a Netgear N150 set to 150Mb mode.  I am using WPA2/PSK AES for security and have the channel set to Auto.
When I upgraded to the 80Mb service I did buy (or rather pay the P&P for) a new router, but it's a terrible looking Plusnet branded one and my Netgear one (which I got with my original 40Mb service) seems to work just fine.
Laptop is a MacBook Pro running both Mac OS X Lion and Windows 7 64-bit and I get the same speed (more or less) under both operating systems.  My wifes laptop (a Dell) running Windows 7 32-bit also gives the same speeds. Our iPads and iPhones also don't get full speed when running tests, which leads me to believe it is the router or a limitation of the Wireless-N.
If I pull up the stats for the WLAN connection in Windows it shows the speed as 72Mbps.
Incidentally, I am sat on my laptop about 6ft from the wireless router with no walls or other obstructions between.  We do have a DECT cordless phone on a shelf below it (maybe 1ft away) but I have tried this switched off as well and it doesn't make any difference.
Is there anything I can do to speed up the connection further?
I know there are overheads on wireless, but I expected to get pretty much the full 80Mb to be honest.

[#2]

72Mbps looks like the max rate you can get using a single 20MHz wide channel - getting the 150Mbps from the Netgear N150 requires using 40MHz of bandwidth, taking up most of the available channels on the 2.4 GHz band. Some wireless adapters in laptops are set to 20MHz only on the 2.4 band by default.
The plusnet branded technicolor is N300, although I've seen a few complaints about it having poor wireless range on these forums recently.

[#3]

How would I make the N150 use 40MHz or is this not possible?
Also, would this imporve if I use the Technicolor router?  Wireless range is not too much of an issue as I am usually close to the router when wanting full speed and have a wireless repeater upstairs where the signal is always poorer.
dick:quote

[#4]

If the Netgear N150 is in "Up to 150 Mbps" mode then 40MHz is enabled. However, the netgear may still decide not to use it depending on the surrounding wireless networks. You may also need to enable it in the adapter properties in device manager - Intel wireless has a "802.11n Channel Width for band 2.4" property, "20 Mhz Only" (default), or "Auto".
The Technicolor N300 would be up to 130 or 144 Mbps using only 1 channel (20 MHz of spectrum).