Well here it is step by step:
Note: This Method is used to Extract Kernels form Stock Rom's Boot.img
First you need to install Python, which is round about 17MBs software freely available on python website.
Step 1:Download the attached Python script named "split_boot_img" from attachments down Below, Extract it and copy to the folder created in Step 2.
Step 2:Create a folder with any name you like. I recommend "boot.img extraction".
Step 3: Copy the boot.img, you want to extract, to the folder you created in Step 2.
Step 4: Run the script named "split_boot_img"by double-clicking and see the magic.
Congratulations!!! Here you go. the "zimage" and "ramdisk" files are extracted.
Now the Conversion Part:
Step 1: Download this IZARC software and install it from Here:http://www.izarc.org/download.html
Step 2: Open the folder created in First-Step 2.
Step 3: Right Click the ziamge File Extracted from boot.img. as in Image 1 in attachments.
Step 4: Select add to archive file from IzArc right click options as in Image 1 in attachments.
Step 5: Now scroll the Archiving type to ".tar" as in Image 2 in attachments.
Step 6: Click the Add button as in Image 3 in attachments.
Last Step: Now flash the "zimage" file created in Step 6 Using Odin.