It does the data purge each day at the time shown in the bottom box on the data purge screen - i believe this defaults to 00:00 (midnight) so once that time has passed the data will be nicely purged and you can run your defag.
All of your commands look fine - the amount of data kept in OpsCenter is controlled in the Settings - Configuration - Data Purge
If you want to change any of these then do so, wait until after the "time of purge" and then defrag the database to tidy things up.
Also be careful when you finally upgrade as there is an issue in 7.1.0.3 where is starts to use only one processor - this is what i thought may be your issue but you say you are on 7.1.0.1 (maybe worth a check anyway - http://www.symantec.com/docs/TECH178219)
On a standard install the reports work for 60 days, on analytics for as log as you like - however the data is kept pretty much forever depending on what you pruning settings are
Hope this helps
