Samsung Galaxy S3 mini — apps wont work

I have had my samsung s3 mini since the beginning of the year, a couple of months ago if fell from my pocket into the toilet. I immediately picked it up took the battery, sim card out and placed it in a bowl of rice for a day or two. It worked fine and has been up until last night, when it all the icons decided not to work. I cant ring, message, receive calls or anything, I can unlock it using my pattern, and swipe across the screens, but not access any of the features, nor settings. When i try and do a hard reset? holding volume down key, home and power, then clicking power up key, the android fella appears and it says Downloading...Do not turn off target!!! but doesnt appear to do anything,
Any advice?
TIA x

— modified on Aug 16, 2014, 10:55:03 AM

thankyou for your reply, done that and got a screen up,
sorry to be a pain , do i select wipe data/factory reset or the option of wipe cache partition first?

thankyou, thing its sorted