You may be aware that plan guides will help the optimizer to perform better and a general recommendation is to use the relevant USE PLAN query hint when the other standard query tuning options are failed. It is also necessary to test through the results you would expect are not upto the mark, when using...
I believe since Windows 2000 server days you can take advantage of Indexing Service that creates indexes of the contents and properties of all files on local and network drives in order to increase file searching speed. It's quite similar to "Find Fast" that ships with Microsoft Office...