All tested!
The news is that it works perfectly on my system and it was quite fun to do the first part again.
This is a worry, because it does point towards installation or hardware issues on your PC.
Anyway....
I played and went through the game:
* Followed the guards
* Got told to wait with the Emporer
* He was killed and gave me the Amulet (not quite in that order

)
* I had to pick my class or something and choose barbarian becuase they are better for hack and slash (i.e. the sewers) and you can change it right before you leave again if you want.
* I went off to find my way into the sewers
* Found my way in
* Killed some rats and goblins
* found my way out
I also saved along the way. One of the saves is right before you exit the sewers so that you have a chance to change your class, sign etc.
If it still crashes on you when you leave then let me know what class etc you want and I'll set it up and exit for you.
Given my success, my feel is that the problem is in your installation (but my fingers are crossed for you!).
- Have you downloaded all of the patches?
- If you have a spare copy of XP, you could always dual boot or install VMware like I did (the game quality as as shown in my pics)
Tim