You can delete/undelete your journal or community at the Account Status page. If you're deleting or undeleting a community you maintain, make sure to select your community from the Work as user menu and click the Switch button.

30 Days: If you undelete your deleted journal within 30 days, all of your entries, comments, and settings will stay the same. If your journal stays deleted for more than 30 days, it is eligible for purging (permanent deletion) from LiveJournal servers.

Visibility: When you delete your account, your journal and profile are hidden. However, you will need to manually delete any comments or entries you posted in other journals/communities.

Paid Accounts: Any paid time remaining on your account is non-transferrable and non-refundable. If you are enrolled in automatic payments, deleting your journal will stop future payments and your paid account time will be credited through your last billing cycle. If you later undelete your journal, you will need to enroll in automatic payments again.