[ec2] Connecting as non Ubuntu User

[Rolo M]

Hiya.  I've recently moved over from using the Eric Hammond images to
the official Ubuntu ones, and am having some probs getting used to the
new ubuntu user way of doing things.  Some of these may be more
general Linux questions so please feel free to point me elsewhere if
this is the wrong place to ask, but any help would be greatly
appreciated.

I've launched an instance (Hardy) and I can connect fine via SSH using
ubuntu@<hostname>.  I've created two other users, one for django, to
run my apps, and one for my username, kolo.

Would it be considered the best way of doing things to continue to
connect via the ubuntu user, and then su to my kolo user account?  I
was presuming it would be best to create a new user account to connect
via, and then disable the ubuntu user? (is there any other problem
with disabling the ubuntu user's SSH access?) Otherwise should I be
telling other people working on the box would be connecting via the
ubuntu user as well?

Presuming I'm best to be connecting via my own account, I've put my
SSH key in ~/.ssh/authorized_keys for both the ubuntu user and my own
user, and infact I can connect with the ubuntu user and authoize with
my key now, but when I try and user my account I get Permission denied
(publickey). (ssh output with -v is pasted below).

What am I missing?  Also, if I su to another user I lose the terminal
colours.  I presume this is because it's not setting the shell
correctly?  All of my user's shells are set to /bin/bash, is there
some other setting I'm missing?  Will my ~/.bash* files get processed
when I su?

Thanks loads for any assistance!  Sorry if it's a bit of a ramble.  Cheers.

Kolo.

--->
debug1: Found key in /home/kolo/.ssh/known_hosts:17
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/kolo/.ssh/identity
debug1: Offering public key: /home/kolo/.ssh/id_rsa
debug1: Authentications that can continue: publickey
debug1: Trying private key: /home/kolo/.ssh/id_dsa
debug1: No more authentication methods to try.
Permission denied (publickey).