Is it ok to run defrag and use the computer normally?

There are two defragmenter programs that are 100% safe:
1. The defragmenter built into Win 7
2. Contig from the Microsoft group-SysInternals.

I use Contig.
To use Contig, go to an elevated command prompt and enter:
Contig E:\* /s /q
to defrag the E: drive. Enter C: for the C drive.

the \* tells contig to start at the root folder and include everything.
the /s says to defrag subfolders
the /q says to run quiet. Nothing will appear on the command shell screen until defrag is complete, at which time you will see the results.

Info you might need:
Contig

Go To an Elevated Command Prompt


Elevated command prompt = Run CMD.EXE as administrator

WIN | type CMD.EXE | do not hit Enter |
in the PROGRAMS list, right-click on CMD.EXE |
choose "Run as administrator" |
Click on the YES button (if such appears)

WIN key = key with Microsoft log on top

for the guru:
WIN | type CMD.EXE | CTRL+SHIFT+ENTER key combo | ALT+Y keycombo

I can't remember if Defraggler has a boot time option, but that is the best way to ensure nothing else is running.

The first one always takes longer as it has more work to do. If you do it regularly, say once per month, subsequent runs should be quicker.

Use Contig. Perfectly safe. Will defrag everything on the drive that which you specify. See post #12