Ok,
ALL reviews and opinions of kernels will be subjective due to differences in use and other factors.
To me, there are a few big things to look for:
1. Are you comfortable with Overclocking your processor. Many of the kernels out now have enabled OC'ing the Snapdragon so some extent. I personally am not comfortable with OC'ing a processor that does not have a built in cooling system. To each their own. You can limit the clock speed on your rooted phone via SetCPU (paid app in the market for root users).
2. Undervolting. Pretty much all of the kernels out there now utilize UV'ing the processor to some degree. I've seen UV values go down to 800 mV. Each processor will be just slightly different and thus will behave differently with dropping the voltage. Some users report no problems at all at the 800 mV level while others are having significant issues.
The methods for installing the different kernels out there are going to be different for almost all of them. Some will require flashing an additional file to keep Wifi working, some don't.
I am currently using this one:
[5.0.6] Desire Cam + Oc-Uv - CyanogenMod Forum
It has the Desire Camera worked into it and is super easy to install. All that is required is to save the .zip file on your SD card and flash it via Recovery. I have not tested Wifi functionality as of yet though. I am also limiting the clock speed to 998 MHz via SetCPU like I mentioned before. I am very happy with this kernel+camera setup but ymmv.
Bottom line, you're gonna have to read a lot to get a feel for what you are comfortable with. If you run into problems or need additional help in figuring out the installs, post in the individual forums for each kernel or come back here and you
will get the help that you need. This community (the Android mod community in general) is probably the best that I have found myself involved in and you will grow to love it as you become more involved in it.
Best of luck and let us know if you need any help at all!