BEFORE you update, run DBCC CheckDB and DBCC CheckCatalog. If there are any errors, do not go further.
After, checkDB with data purity, update all statistics, update usage. Order doesn't really matter, but consistency checks first are best.
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