SQL Transaction File

I have a transaction log that has 438 megs in it. I tried to reduce the size but I don’t think I did. I did “DBCC shrinkfile/emptyfile”. I then tried to “alter database and remove file” but the system will not allow me to remove a primary data file or transaction log which is a good thing. I went back into explorer and the size of the log had not changed. How do I reduce the size to the transaction log, I need the disk space? Also, in SQL Enterprise Manager the transaction log space used is 13.7mb and the free space is 414.1mb. What does this mean?