Please read through this - Managing Transaction Logs[/url] and - http://www.sqlservercentral.com/articles/Transaction+Log/72488/
Don't just shrink or change recovery models without analysing and knowing the effects of the actions.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability