Which debugger is best?

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Is now really outdated, but also W32DASM used to be good.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