I wrote "So all is good, Lx IS on 4, Swap on 5." I did mean 4th physical and 5th physical, not the MBR order.
I'm moderately sure that that error msg about ntoskrnl missing comes from winload.exe, the pgm that loads the windows kernal and then hands to it. I think with W7 it goes bootmgr reads config data, loads winload, winload loads the kernal and drivers. I rather think that Grub has taken over the W7 boot manager's job by installing itself there, and messing up boot. But then you can get to the W7 boot manager via a different Grub link, and that works. So... I'm confused, but since your Active partition is the Dell Recovery, I guess Grub is there, and possibly the bad W7 link points to the wrong partition or more likely is just plain bad, so reinstall/fix Grub (this lil duck cannot do that), and the good link points to the W7 partition and its boot manager (bootmgr used is in the volume boot record of the selected partition). A normal W7 boot would involve the Active partition and its volume boot record. Ok, I admit it, I'm lost, and I find the Grub config data too arcane to get interested in.
Can you live with it? Else it's off to the Linux forum with you.