Hi Promod,

Say you have following records

Parent__c
Child__c

//Fetch all childs 
List<Child__c> allChilds = [Select name,Id,lookupName__c from Child__c ];
//Parent Id set
Set<id> parentIdSet = new Set<id>();
//Create parent Id set 
for(Child__c childs :allChilds){
	parentIdSet.add(childs.lookupName__c);
}

//Fetch all associated parents
List<Parent__c> allAssocaiatedParents = [Select name from Parent__c where Id IN : parentIdSet];

//For loop to set data
for(Child__c childRec : allChilds){
	for(Parent__c parentRec :allAssocaiatedParents){
		if(parentRec.Id == childRec.lookupName__c){
			myWrapperClass wrapRec = new myWrapperClass();
			wrapRec.parentsToFetch = parentRec;
			wrapRec.childsToFetch = childRec;
			wrapperList.add(wrapRec);
		}
	}
}
//Wrapper list 
public List<myWrapperClass> wrapperList {get; set;}
//Your wrapper 
public class myWrapperClass{
	public Parent__c parentsToFetch{get;set;}
	public Child__c childsToFetch{get;set;}
	public Boolean selected {get; set;} 
	public myWrapperClass() { 
         selected = false; 
      } 
}


//Updating your records

public list<Parent__c> parentListToUpdate = new list<Parent__c>();
public list<Child__c> childsToUpdate = new list<Child__c>();


//Say you have an action from page as updateRecords
public void updateRecords(){
	//go for a for loop
	for(myWrapperClass wrapRecNew : wrapperList){
		// Only update selected records
		if(wrapRecNew.selected){
			parentListToUpdate.add(wrapRecNew.parentsToFetch);
			childsToUpdate.add(wrapRecNew.childsToFetch);
		}
	}
	update parentListToUpdate;
	update childsToUpdate;
}