Kernel "corruption" on phone ??

[Weapondrift]

Two nights ago I flashed a custom kernel from Ziggy at XDA and PPCG when I flashed his kernel I was running CM6stable release. I backed up my rom in Rom Manager and then rebooted into Clockwork using Rom Manager. Since I like to keep everything organized I didnt rename the .zip file because I already had Hydra v1 overclock kernel (running with no issues) and didnt want to confuse myself. Anyway, I "choose .zip from sdcard" in Clockwork and then applied Ziggys kernel. I tapped the power button to back up one screen to "reboot system now". Heres where the trouble began, the phone rebooted and I got alot of black lines which remind me alot of "corrupted data" is the bast way I can describe it. I was unable to unlock my phone from the screen nor use my screen at all for that matter. When I pressed the power button I got the normal list of options when you hold down the power button but naturally I was unable to use the touch screen to select anything.
I tried this kernel with a few different roms to see if the same thing occured/ Jager yes/CMRC3 yes/ Skyraider yes/Skyraider RC3 NO/. After each one I always reverted back to Hydra Kernel v1 and it worked just fine. However this morning I reflashed CM6.1 and tried Hydrav1 again and the same "corrupted data" occured.
Any ideas why this would happen and if there is a fix? Any help is much appreciated.

[Weapondrift]

[jkhonea]

This may sound stupid since I'm new to rooting, but is it possible to flash a different kernel over the top of this one to essentially overwrite it?

[tp7six]

JK that is possible through SPR and CWR this is how most people find the best kernel for themselves by going through them until they find the one that runs the coolest and smoothest

It is a simple overwrite

[Weapondrift]

JK not a stupid question at all and what Parker said is right its just a simple over write. My ultimate question at least the answer I am loooking for is why did this occur? Especially when theres not that much of a difference between Cyanogen6 and Cyanogen 6.0.1 and yet the same kernel I use wont work with the newest.