from what i understand from ur post is that i can still get the privious sms...its only the matter of folder that i ll create...am i rite?
Understand that there are 2 backups: -one that itunes auto create and overwrite everytime you connect you iPhone to your computer and
-one that you can create by your self. If you create a backup which you name let me say XYZ Backup 10/10/10 all the informations present in your phone at the moment you are making the backup will be save in that XYZ backup. At the same time, itunes will automaticaly over write it own backup. Now after creating that XYZ backup you decide to delete some 10 contacts, 10 SMS, 10 mms, from the phone. When you reconnect your phone to your iTunes, It will overwrite the existing iTunes backup to the actual informations present in the phone which of course will result of an auto itunes backup with 10 contacts missing, 10mms missing, 10 SMS missing etc...
But your backup XYZ will still be there and still having those 10contacs, 10mms, 10sms informations in it.
The day you will want to get that those 10 contacts, 10mms etc info back into your phone, you will connect your phone to your iTunes and then right click on your phone icon and select restore, a dialogue box will display asking you to chose what backup you want. You have a choice between your XYZ Backup and the iTunes backup. And ofcourse the files you need are in the XYZ backup so that's what you will select and restore it into your phone and those deleted files, 10mms, 10sms, etc... will all be back into your phone.