Reading between the lines, you either wanted to:
1) delete only the linux partitions of a multi boot disk (keeping windows OS?).
2) delete all partitions on your disk and reinstall a new OS.
If 1) and you are now trying to boot windows with a broken grub, you probably want to restore the windows boot loader. If so, boot off a windows CD/DVD, go into repair mode and enter:
fixboot c: (or whatever drive you boot from)
If 2), then need to either reinstall a new OS or (if there is still another linux partition) fix your grub installation with either of these instructions:
Fix grub boot errors or grub2 reinstall