This is all either used by me, or recommended by someone I trust.  And it tends to be geeky.  Bye, Angie.

Editor of choice is Notepad++.  In addition to being able to load big files fast, and understanding XML files, this one does column cut/paste and can show only lines containing (or not containing) whatever’s on the clipboard.  Used daily.

XML Marker makes it easy to work with XML files.

AutoRuns will help you see what’s going on when your PC starts.  Very thorough.  From the good guys at Sysinternals, now owned by Microsoft, but still producing good stuff.

Wireshark will help you out if you’re trying to go deep in some networking problems.  It used to be called Ethereal.

And a couple free utilities from Bare Metal software: BareTail and BareGrep.  I haven’t used these yet – my work of this type is on Unix – but they come recommended.