Have you tried taking the battery out for 30 mins then booting the phone up? Sometimes that can help. You could try a factory reset but you'd have to make sure you back up your contacts/sms messages. The contacts should be backed up via Google if they're linked to your Google account. As for SMS there are a few apps in the store that can do that for you. If you need to do a factory reset then goto settings>SD & phone storage>factory reset. Everything on your SD card will be safe but everything else will be wiped. So any apps you've installed will be gone, but you can reinstall them afterwards. As for rooting you could go that way but I'd try the above first and see if you solves your problems. If not come back here and look at the 'All things root guide'. It will explain everything you need to know. If you get stuck then dont be afraid to ask!!