Unextendable Desktop

Hello,

I have an accer aspire one and I just bought a HDTV to use as an external monitor. I have attempted everything that I can think of to extend my desktop. The only options that I get are the desktop clone or pick one monitor. I have Windows 7 and the Intel Graphics Media Accelerator Driver for mobile. I saw a video on Youtube of a guy with the aspire but his OS was older. I found a how to on the internet with the correct OS but the option to extend the desktop in the drop down of the Control Panel-->Appearance-->Display-->Change display settings:Multiple displays, does not give me the option to extend. Could you please provide some assistance with solving this issue. I appreciate any help at all.

Thank you in advance,

Quincy Manzey