Concurrent backups (full and transaction) and testing recovery model
Working out which Log Backup to restore is all based on LSN's. You have to apply all log backups since the full (or differential, but you didn't mention them) backup, including log backups taken while the full backup was in progress.

There is no danger in trying to restore a log backup out of sequence, it just won't work. Kin answered above how to find the actual log backups you need to restore.

It's important that you have a continuous chain of log backup files. If you are missing one, or if it's corrupt then you can't restore anything after that point.