What OS are you running? What version of Graphics Driver?
Go here and check to see if you have the latest driver, http://www.intel.com/support/graphics/detect.htm
Then run the Intel TV Wizard to configure your system with your TV. To open TV Wizard, right click on desktop, click TV Wizard on context menu. From there its pretty straight forward.
Windows 7 x64. I have tried with graphics driver 2057 (from intel site), 2021 (from windows update), and 1995 (the one that came on the CD from the board mfgr gigabyte). I don't see an "intel TV wizard" when I right click on the desktop. There are two options that pertain to graphics "graphics options..." and "graphics properties". The properties menu item takes me to the control panel. The other one allows screen rotation, hot key assignment, etc... Where might I get this intel tv wizard?
OK, that explains it. Win 7 64 bit is not supported by TV Wizard. It is only available with the 32 Bit OS's.
With the 64 bit OS, you need to use the Intel Graphics and Media Control Panel. It sounds like you have done all of the following, using the Custom Resolutions and Monitor/TV Settings tabs.
Try to set the Custom Resolutions Advanced Settings if you can get the correct values for the Samsung LNR268WX to input. Does your users manual have the values? Possibly Samsung's website?
I'm not sure if this is related to your problem, but the 1360 x 768 resolution is actually a bit beyond 720p resolution (1280x720). A 1080i TV I use with a PC considers it's native resolution to be 1360x768, although it is only a 32" TV. Does your TV's manual say anything about connections to PCs? My graphics controller lists another resolution for 720p as 1176 x 644.
Also, you did not mention the refresh rate, such as 60Hz, could that be an issue in this case? Is your TV a plasma type? That may require a certain refresh rate.