Which debugger is best?

[piccolo]

An odd one which is sometimes forgotten but which isnt at all bad is to use the open watcom compiler with its debugger. It is totally free and it used to be a payware thing... Just check the open watcom site for it..

[Evilcry]

Debugger choice depends on complexity and particular context, basically OllyDbg2 cover a wide range of situations.

But for complex environment debugging WinDbg + scripting is "the best", both on ring3 and ring0 situations.

It's a bit unfriendly for a beginner, but I strongly suggest to learn also this debugger

Easy drivers, can be debugged with Syser.

Also ImmunityDebugger is pretty good: basically is OllyDbg with some tweak such as a built-in pythonAPI, a function graphing tool and a heap analysis tool.

Ida pro is really powerfull, but not as immediate and easy to use as OllyDbg; moreover, OllyDbg's plugins are actually useful.

Is now really outdated, but also W32DASM used to be good.

Finally, as stated above, if you want to get a bit more "in" the OS, there's Syser for your comfort. Syser is SoftIce's little up-to-date brother (as they say "Softice is left. Syser will continue.").