Is there any way i can change my whole account username and not just my display name?

[Innula Zenovka]

You can't change your username, I am sorry to say. 

It shouldn't be necessary, though.  It is perfectly simple to make scripts use people's display names.   There is nothing complicated about, for example, 

 

default{	state_entry()	{		//llSay(0, "Hello, Avatar!");	}	touch_start(integer total_number)	{		key k = llDetectedKey(0);		llRegionSayTo(k,0,"You just touched me, "+llGetDisplayName(k)+"!");	}	}

 

[Innula Zenovka]

You can't change your username, I am sorry to say. 

It shouldn't be necessary, though.  It is perfectly simple to make scripts use people's display names.   There is nothing complicated about, for example, 

 

default{	state_entry()	{		//llSay(0, "Hello, Avatar!");	}	touch_start(integer total_number)	{		key k = llDetectedKey(0);		llRegionSayTo(k,0,"You just touched me, "+llGetDisplayName(k)+"!");	}	}

 

[Rolig Loon]

Display names are a convenience, sort of like having a nickname in RL, but can't be used for anything important.  After all, people can change Display names every week, and there could be dozens of people in SL calling themselves LuckyBob at any given time.  Your username is unique and can NEVER be changed, so we can be sure that we are dealing with the one and only Rikeau. That's why many people (like me) prefer to set their viewers to see your username instead.  Scripted devices like vendors and visitor counters look for your username for the same reason.  Some will show your Display name as a courtesy, but don't count on it.

[Lindal Kidd]

The only way to "change" your username is to create a new account, with a new username.  If you really despise the name you have now, do this soon, before you collect a lot of things in your inventory and a lot of friends.  It's harder to start over when you have a lot more time and effort invested in your avatar.