OS X :: Restoring/deleting TM Backups?

I needed to delete one folder from 4 back up days in time machine. It wouldn't let me delete just the one folder because it kept saying that I can't modify backed up items. I ended up putting all 4 back up days in the trash (which required my putting in a password). When it prepared to empty I saw there were over 60,000 items and I got scared that something important might be in them. Now, the 4 particular days are not that recent, and not that old. About midway through all my back up days.

If I delete all 4 of them, will the data in the back ups before or after those days change? Will it affect any of the data I have now?

I've also tried removing them from the trash and putting them back in time machine after I chickened out. It wouldn't let me do that because it once again said that I can't modify backed up files. When I pressed authenticate to put in my password, I got another error message that said I can't do it.

So if I can't empty the trash and I can't put the files back, what do I do?

This is all because of one folder that happens to appear in 4 back up days. My ideal scenario would be to put back those 4 days where they belong in time machine, and remove just the one folder from those days.