You should reflash (firmware and eMMC to be safe) and do not install anything except maybe conky to monitor your device.

Use it for some hours or a day and see if it freezes at all. If it doesn't freeze, it's the apps fault. Then install applications little by little (one or two at a time) and test which is the culprit.

It could be widgets though. even though I have many widgets installed I only have 4 enabled: App search widget, media player widget, the sms widget and the rolling eyes. The widgets used to cause freezes on my phone too.