It sounds like the updates page is not loading properly. Have you tried refreshing that page in CF Administrator? Also, you might try restarting the ColdFusion service. You might have a proxy/firewall issue as well. Here is the direct download link for the update: http://download.adobe.com/pub/adobe/coldfusion/hotfix_010.jar.
You might find this CF blog useful:
Apart from the suggestions provided above, please make sure you have proper permissions on updates.xml at C:\ColdFusion10\cfusion\hf-updates\.