Just a quicky as I've learnt loads from posts to this...
Note that where you do a 'Search for Files and Folders' 'Containing text' NOT ALL FILES are actually checked!!!
To verify this for yourselves; create a .txt file and slap some text in it (IE. Hello World) and save it.
Then open the folder and search for files (hit F3 or the Search button).
Enter some text that is known to be the new .txt file (IE. ello)- works ok.
Now rename the file (from the command-line, so that XP doesn't track the filename change) and repeat the search - hey presto, no results to display!!
To fix this I've created a utility - just search Programmers Heaven for 'Search Checker'.