The default kernel provided version 0.4.1-beta2 (and more recent versions) is brand new. It’s based on new patches and it has a new configuration. It now includes support for SMP and ACPI. This kernel should solve problems for users that were unable to boot SystemRescueCd. So if you had such problems you should give it a try. This kernel is still based on 2.6.22.9, I will switch to 2.6.23 later.

This new kernel is the default choice. I mean the boot images for this new kernel are rescuecd for 32bits systems and rescue64 for 64bits systems. The kernel used previously has been renamed to vmlinuz2, this is the alternative kernel. So if you were happy with the default kernel in version 0.4.0 and you want to keep it, you should use the vmlinuz2 boot image.

All the kernels have hard-disks controllers (ide-pata / sata / scsi) and the network card drivers built-in. I think this is important for a rescuecd to have these drivers built-in because you can useone of these kernel to boot a linux system installed on your hard disk (in case your boot manager is broken) and you are sure to have problems if the important drivers are compiled as modules since the systemrescuecd modules are not installed on your linux partition. It’s also necessary to have kernels built-in in order to get the network booting via PXE to work. This kernel has also the most important file systems support built-in, and it supports Reiser4.

So you should use the default kernel (rescuecd or rescue64) with the new systemrescuecd versions and use vmlinuz2 only in case of problems.