EQ2 takes no prisoners when it comes to system requirements so if your rig is bare minimum, you will be probably be able to play but only at the bottom setting and with all the "pretty" stuff turned off. In addition, you will undoubtedly experience heinous lag in cities, towns and other heavily populated zones. You might as well forget about traveling in dungeons as well...
To run smoothly, you will need:
3 GHZ CPU
!-2 GB ram
128-256 MB vid card
Can you get away with less? Yes, but it won't be pretty!
This might be a good time to start thinking about a new computer!