Default change keylock on desire

hey there,
is it possible to change the Sense keylock? for example put the slider higher? because atm I sometimes call people, start apps as soon I put the phone in my pocket. and yes I know I could enable the pattern lock but I really hate it :)
LG Optimus 7 Mango
old Phones:
HTC Diamond
HTC Touch
SDA Music (HTC Amadeus)