MBR Checksum Error

Evening:

About a week ago, my phone was hijacked by a rogue app. I somehow got this app when trying to update the "360 Security" app.The rogue app is qihoo security This particular rogue app will not delete and does not stop running; thus, I cannot access any other part of the phone's menu...i.e. any other apps or files. So, obviously, I cannot delete it or it's files. I tries to reset to 'default settings" but in doing so, it did not rid the phone of that app. And when in default reset/download mode, I noticed it posted a MBR Checksum error??? So, 1. How do I delete/disable the rogue app? 2. Is there a way to "tether" the phone and possibly 'wipe" the O.S. and reinstall another? Gotta say, this is a weird occurrence!

phone specs: Samsung Anycall GalaxyS model shw-m110s-----FroYo 2.2
THANKS:
Rick