|I trust you realise that most programs start from the registry itself, not the startup folder. Ones that appear in startup are usually shortcuts to the actual program exe file. These shortcuts are either in the "named user" or "all users" area of Documents and Settings.|
Sure you can do things with batch files to create delays but without details about the exact programs you wish to delay we can only generalise. The approach would be to create a batch file with a delay to start each program exe file required. You then make shortcuts to the batch files you have created and put those in the startup folder instead of what is existing, chosing "named user" or "all users" locations as required.
In this webpage scroll down towards the bottom of the page and find "Creating a batch file delay":
I don't think either the Choice command or the Sleep command are native to XP so one or other of those tiny files would have to be downloaded. The Choice command gives a max of 99 seconds but could presumably be cascaded.
As far as I am aware there is no feature in the registry to delay the start of any program so your preconception is false.
How to know you are getting old 3:
You start converting your age to hexadecimal