Never mind i sorted it myself ?
On the phone to netgear and they said they had not encountered the problem before,dont think so because if you do a Google search for Playstation 3 /Netgear/Fragment problems you will find 100s of posts regarding the problem.
Anyway while waiting for a call back from Level 2 support from netgear i happened to come across a thread regarding a similar problem which i tried out.
Its regarding the Multiplexing setting llc-based and VC based,new router was auto configured and put this on llc-based so i changed it to VC based and then ran the playstation connection test and it sailed through with flying colours.
So i checked everything else after the change just to see i had not mucked something else up and all seems ok,then checked the Multiplexing setting on previous router [older] and it was on VC-BASED so that explains it.
What does surprise me and Netgear themselves is why when i connected the router yesterday it did not detect what setting it should be on regarding my isp like my previous 2 older routers.
Should work for technical support with netgear me thinks
Anyway thought i would post this just in case someone has a similar problem in the future ,also told netgear may be they should put this fix right with a firmware update in the future.