My k800i giving problems after 2 and a half years of usage.. now problem is that my games stored in memory card just simply went missing.. i didnt remove any.. plus sometimes my phone hangs until i have to remove the battery to make it functioning again.. and the phone response damn slow nowadays.. lagging i must say.. what should i do? does this problems tends to happen to k800i? Do advice.. thanks in advance

Ic.. Well did clear up junks from phone and memory.. lag problem gone but still there are no trace of the games.. Neways thanks!