I've got the original CD version of the game, which I've had from new but never finished back in the day.

Having reached the Ice Caverns, but not yet visited the Faerie Realm, I have come across an area I cannot access without the game freezing. It is near the Ice Queen's throne, which I can see in the distance, and I've tried accessing it from each side of the square area, but it freezes no matter what I do.

I've since updated to version 1.2 but every time I try to load my save game, the screen goes black and I can hear music but nothing else happens.

Can anyone offer any help on how to solve this, as I don't really want to start over?

That's a shame. I'm not quite sure what could be done. But you may have to start over. It shouldn't be too bad though. The game is pretty predictable with how it challenges the player. So with some strategy you could be more powerful than before by the time you reach that level once again. Practice shields early on, maybe even hang out at a fountain of thera in one of the towers and heal up after going out and letting the Sharga's swing out you for a bit. And then max your skills on the spent piece magic flint in the dwarven clan hall. It should take 30 minutes to an hour and a half. Depending on how you played till then.

I'm sorry this isn't a fix for your save. I wish I could do more. I don't think there's any good save editors out there that let you edit your inventory/etc. Good luck, and I hope you keep playing in spite of this setback.