Firefox is only available as 32-bit for Windows OS's. A 64-bit version hasn't been released.

As far as Firefox crashing, please follow the steps below to provide us crash ID's to help us learn more about your crash.

1. Enter about:crashes in the address bar (that's where you enter your website URL) and press Enter. You should now see a list of submitted crash reports.
2. Copy the 5 most recent crash ID's that you see in the crash report window and paste them into your response here.

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

No that is ok.

Firefox for Windows is a 32 bit browser, although developers do have experimental 64 bit builds available. On Linux and Mac ordinary users may install 64 bit versions.

Crashes and hangs are separate problems. If you have crashes please paste a couple of Crash IDs into your next post.

1. Troubleshoot Firefox crashes (closing or quitting unexpectedly)
2. Firefox hangs or is not responding - How to fix

• Or maybe Warning Unresponsive plugin - What it means and how to fix it
• Does killing the Firefox process in TaskManager allow Firefox to restart ?
• What if any error messages are you getting ?