Now been told that security message in driver message center means ignition prolly going bad, if it fails to engage starter couple times before turning over and starting, would this confirm it's the ignition switch, and would I need new switch and cylinder or my cylinder go on to new switch, and thanks for any help you give.....in advance

 

I would do the security relearn first. If that fixes it, then it is probably your ignition switch. Relearn is really simple.
1. Try to start car.
2. Leave key in the On position until you see the security light is no longer flashing (usually 10 minutes or so).
3. Turn key to off position. DO NOT REMOVE THE KEY.
4. Wait 15 seconds at least.
5. Try to start car.
6. Leave key in on position until the security light isn't flashing anymore.
Etc, etc.
You need to repeat that 3 times. Start, on until light is gone, off with key in for 15 seconds. After the 3rd time, the car should start fine.

If it is the ignition switch, you would need to replace the cylinder and the switch. I just had to go through this, it is REALLY easy. This video shows you exactly how to replace it, then after that you would need to do the relearn again. I would recommend buying one of the OEM ignition cylinders, then having a local mechanic set it up for you. Much cheaper then having a GM dealer do it, and you don't have to do it yourself.