Help screen issue

[kaiparaghu]

When I connected internet from my Samsung Ace GT-5830, It entered my Picasa and downloaded some photos. Now after disconnecting internet also it shows some photos and empty thumbnails. When I am unable to delete these picasa photos. How to do it.

 

[kaiparaghu]

When I am on a call, the screen goes off. When I want to cut the call, I have to press Home key. When I do so, it takes me to home screen, but not the dialed number screen. How to address this.

 

[Gammer]

When I am on a call, the screen goes off. When I want to cut the call, I have to press Home key. When I do so, it takes me to home screen, but not the dialed number screen. How to address this.

That's your proximity sensor. It automatically turns your screen off when it's next to your ear,when you take the phone away from your ear it should turn it back on( i have a delay of 1-2 seconds).
If you're doesn't come back on at all then you have a problem with the proximity sensor.