Can I delete older Time Machine backups?

Question

I have an extensive set of Time Machine back-ups on an external drive for a machine that I no longer own. I want to keep a back-up of that machine...but just one copy, not the multiple copies that exist now.
My first thought was to simply delete all of the backup folders except the most recent one. But I don't know enough about how Time Machine works to know if that approach will work, or if the most recent backup somehow depends on all those previous folders, and I'll end up deleting important content.
Can I delete the older folders? Is there a way to "compress" the backups so I have just a single, last snapshot of the machine?

Answer 1

As Kappy says, you can do this via the TM interface, and from another Mac, but it's rather tedious.
+Enter TIme Machine+ won't show you the backups from another Mac. But if you hold the Option key down while selecting the TM icon in your Menubar, it will change to +Browse Other Time Machine Disks,+ that will.
Locate the backup you want to delete via the "cascade" of Finder windows.
Then select the "gear" icon in it's toolbar and +Delete Backup.+
You'll see a confirmation prompt, then one for your Administrator's password.
When you delete an entire backup, it will disappear from the timeline and the "cascade" of Finder windows, but it will not actually delete the backup of any item that's also present in any other backup. Thus you may not gain much space on any one backup. The deletion is usually fairly quick, but sometimes quite lengthy (if you exit TM, you may see a progress bar for it). Unfortunately, you cannot predict which will be quick and which won't.