Hi guys..dhd users..i need some help here..

Dhd details:

Stock room still virgin..never rooted..currently on latest sense 3.0 android version 2.3.5..sofare number 3.13.707.4

in past week until now, i hava faced problem in dhd gallery..the problem listed as below:

a) i can open the gallery...but i cant scroll down to see another folder..everytime i scroll down it will automaticly go to the top..same goes when i open the folder..i cant scroll down to the pictures below..as it always go to top..this problems bother me as i cant view the pictures..

b) when i open any pictures via gallery..normal thing is once i tap it will show 5 icon below of the pictures..such as share..delete and etc..but mine..when i tap..the icon only pop up and then goes missing again..so it hard for me to use the sharing function..

because of the problem i need to use third party app to view my pic gallery..but what i used now lack of sharing function to social network...

What i had tried but failed.. :
a) soft reset : pull out battery, sim, sd card..
b) uninstall some apps that related to gallery such as gallery lock pro..but the problem still persist..
c) scan and find sd card using market apps..
d) scan my phone using lookout mobile security..but found nothing affected..

I assume my stock app gallery got bug..but i dont know how to confirm it..is it a way i can resintall htc gallery apps?

P/s: i dont want to root or custom rom..i also dont want to factory setting as i dont want to lose all my data..im still in love in sense and prefer to stick with stock rom..

Your opinion and help is much appreciated..

Thanks...