I have installed Ubuntu from wubi.exe along-side windows, and I am a new user to it.
If my kernel has an error after modifying it and replacing the previous one, does the "safe" option in my bootloader recover my kernel?
If you build your kernel following the proper procedures for building Ubuntu kernels (I don't know what they are), then when you install the resulting
Recovery mode isn't a special kernel. It just boots a minimal system, using whatever kernel it's paired with.