kernel / grub problem after running Update Manager (10.04)

After a clean install of 10.04 (Lucid) I ran Update Manager. There is now a problem with the kernel or grub. When I try to run Synaptic Package Manager or Ubuntu Software Centre I get a message saying:

“E: dpkg was interrupted, you must manually run 'sudo dpkg --configure -a' to correct the problem.

E: _cache->open() failed, please report.”

I have tried running the “sudo dpkg --configure -a' “ command in a terminal, but it always gets as far as

“kelv@kelv-desktop:~$ sudo dpkg --configure -a

[sudo] password for kelv:

Setting up linux-image-2.6.32-30-generic (2.6.32-30.59) ...

Running depmod.

update-initramfs: Generating /boot/initrd.img-2.6.32-30-generic

Running postinst hook script /usr/sbin/update-grub.

Generating grub.cfg ...
”

then freezes. I now only run Ubuntu (i.e. no more MS Windoze) but I know very little about the command-line side of things, so if anyone can help, please give step-by-step guidance if / where a command-line input is needed in order to solve this problem. Many thanks in anticipation.