There are a couple of options for connecting a computer to a tv. For the Toshiba 19AV600U, you can use the HDMI or VGA ports, depending on your computer. First identify the available video ports on your computer. Make sure that the port is active. (Some laptops disable the external video port to save energy; this may need to be enabled in the BIOS). Get an appropriate video cable (VGA M/M, HDMI to HDMI (M/M) or HDMI to DVI (M/M)) and an audio patch (3.5 mm M/M) cable (if using VGA or HDMI to DVI) and want to use the TV speakers. Turn off both the computer and the TV. Connect the two devices. Then turn on the TV and set it to the desired input.
Now turn on the computer. If the TV is the only video output device connected, a modern Windows machine will probably correctly set the screen resolution correctly. Make sure that the refresh rate is set to 60 Hz for most resolutions. If your computer is a laptop or is connected to another monitor, you will need to adjust the graphics output. On my HP laptop with Windows 7, I right click on the desktop and choose Display Properties. This lets me select output to the internal screen, external screen, an extended screen, or having the same output on both screens. The last two work best when the screens have the same native resolution. After selecting the display, an "are you sure" message will come up. Click OK; otherwise the computer will revert to the previous setting. On my desktop with Win7, this is under Screen Resolution. You can also get here through the Control Panel > Appearance and Personalization. For other versions of Windows, the path is slightly different. (I'm not sure of the routine for Unix or Mac OSX.)
If you want a wireless connection to the TV, you will need an appropriate device. Follow the directions for that unit. (HDMI wireless devices exist but I have never used them.)
The manual for the TV is available here: http://a248.e.akamai.net/pix.crutchfield.com/Manuals/052/05219AV600.PDF
. See page 18 and page 51 for screen resolution choices.
I hope this helps.