So I've been a bit of a slacker and fallen behind on OS upgrades.  This is where I am:

james:~$ uname -a
Linux www 2.6.18-6-xen-686 #1 SMP Sun Feb 10 22:43:13 UTC 2008 i686 GNU/Linux
james:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 8.10
Release:        8.10
Codename:       intrepid

Will I hit kernel problems if I upgrade the OS without the kernel, or the kernel without the OS?  
Is there a recommended/tested kernel package?

Thanks

James