Failing to delete the account

Facebook does not support account merging. You have to manually copy what you want from your old profile, and then delete it.

You should be able to regain access to old account via http://www.facebook.com/#!/help/contact.php?show_form=hack_nologin_access - I've never used this and I don't know what they procedure is however. I guess once you have convinced them your are who you say you are, they will change the account email address, which will let you reset the password as normal.

To remove a friend:

1. Click "Account" on the upper-right part of the screen
2. Click "Edit Friends" (first option under your profile picture)
3. On the left sidebar, under the "Lists" section, click "Friends".
4. Find the friend(s) you want to remove (you may need to click the arrows at the top or bottom of the list) and click the "X" button on the right.
5. A message will pop up asking if you really want to remove them. Click "Remove".

If you want to block someone, so they can't contact you at all:

1. Click "Privacy Settings" under the "Account" button on the upper-right part of the screen
2. Under the "Block Lists" section at the bottom of the page, click "Edit your lists".
3. Type the name or email address of the person you want to block, and click the corresponding "Block This User" button.
4. If you want to unblock them later, follow the same steps, but click the "(remove)" link next to their name/email address in the list.