Random car issues

I have a 95 camaro z28 with 119xxx on it. It usually will lunge forward when I'm coming to a stop and it down shifts into first. It idles around 800 instead of 600 which I hear is normal. Also it very rarely stalls out when either just taking off from s light or in the middle of driving. Another issue is that it sometimes doesn't start the first time, it'll either just keep cranking or it'll almost start then bog down and then it takes a few times to start it, usually with my foot on the gas. My coworker also noticed a noise coming from my lifters, or so he thinks anyway. I know my o2 is bad on the drivers side. I have no idea if that's could cause those issues or if it would be something else