68k emulation is transparent. But note that 68k software that doesn't play nicely with the system or that bangs amiga chipset won't work too well.
But programs like ImageFX, TVPaint, Ibrowse, Magellan, and many many others work just fine (and fast).
Now, if you don't know what to do except browsing, you could try movie playback with MPlayer, or some games/emulators if you feel like playing