Could you please let me know the following details:
1. Which version of Adobe Reader are you using. You can get the same by clicking Help > About Adobe Reader
2. Which browser are you using to view the PDFs online
3. Also, since you are on a 64 bit system, please ensure that you are using the 32 bit version of the Internet Explorer.
1. I'm using Adobe Reader X.
2. I'm using Firefox, but have also tried Internet Explorer, and I get the same thing.
3. Um, shouldn't I be using the 64 bit version of Internet Explorer if I have a 64 bit system? o.O Or was that a typo? :3 If so, then I am using the 64 bit version of Internet Explorer. And, naturally, Firefox doesn't have a 64 bit version, so it's just 32 bit.
Actually you need to run the 32 bit version of IE, since there are no separate plugins for a 64 bit version.
Could you also try manually deleting all the files/folders from the installation directory (it would be C:\Program Files (x86)\Adobe\Reader 10.0 by default) EXCEPT for the "Setup Files" folder. Now try and repair the application from within the Control Panel (Programs and Features) and see if it resolves the issue.
In the meanwhile, you could try the following workaround to circumvent the browser crash.
1. Open Adobe Reader and goto Edit > Preferences
2. In the Internet Pane, uncheck the option for "Display PDF in browser"
3. Close all windows and try accessing any PDF in the browser. It will now ask you to save the file on your hard disk rather than opening it in the browser.