How did you delete them?
If you deleted just the shortcuts in the Start Menu, the programs themselves will not be deleted, and you can get the shortcuts back.
What computer Operating System are you using? Please give more details on your computer specifications.
I deleted a number of program files including my defragment ,maintenance wizard,all my accesseries, I thought they were in the start up menu,and slowed my pc down. . I still have the original folders and files in explorer but I can't find all my maintenance software etc........ help please I want to put them back in the start up menu