[Five]

yes, you're understanding... crack all those tabs, unless the tapes are blank!

now for the next part... the 'hole beside the hole' indicates that it is a chrome tape. if you dig up the cheapest cassette you can find or some official release cassette compare how it looks different from the chrome tapes above. similarly, for metal tapes there's a hole close to the middle (one for each side). more expensive tape decks detect not only the record enable/disable tab (the ones you're breaking) but also use the other holes (or lack thereof) to detect the type of tape: normal, chrome or metal. a special filter is applied to chrome and metal tapes by the player, or on cheaper decks/walkmans you have a two-position switch for either normal or chrome/metal playback. I believe it sounds best to play back the tapes the correct way, but some people feel differently... so you can tape over the 'chrome' or 'metal' holes to temporarily trick your tapedeck into playing it back without using the correct filter (a bad idea 99% of the time imo, but in case you want to give it a shot...)