Well, both issues you reported (sprite not displaying, and now C2 crashing on new/open) were already reported before and so far always have been resolved by the installation of the correct/newest drivers.
Apparently, so far you dld/installed drivers and it weren't the correct ones (or they are just badly programmed). Try to uninstall them all and proceed to install (again) the newest drivers available.
You can also try a full reinstall of your OS (from scratch with a format) or even updating to a newer OS (win 7 if possible).
From there, apart from having a direct access to your computer to be able to see directly "on site" what's going wrong, there's not much more that can be done support-wise.
Once again I refer to Ashley's last blog article, you might be stuck with a computer whose manufacturer doesn't support on the drivers/compatibility level.
Would you have access to another computer and try installing C2 on it ?
Do sprites display correctly? Older ati cards have crummy drivers for opengl. I have an ati card on my laptop that is about 4 years old and for me re-sized sprites become transparent. The latest drivers did not fix it but for me tiledbackground objects display correctly. You can try to tweak the opengl display settings for your card as that sometimes can affect it. Another thing you can try is http://titaniumgl.tk/, which wraps opengl to directx.