*solved* I figured out and thought I edited this last night... the lcd tv was for some reason set to 16bit colour... changed it to 32bit and hey presto. Aero is back!
Thanks though steadfast
. I did try everything else... multiple driver installs etc. I think Microsoft want to even make note of this, as they couldn't pick anything up with the troubleshooting transparency however its something quite simple that effects its operation!