Steven -
While what Mark says is accurate, there are two big things you need to be cautious of.
1. If you delete all start and top times, that could have a big impact on historical reports that use that information for job costing.
2. If you uncheck all the 1000s of waiting for sync approvals then they'll *all go straight to QuickBooks*. Wait for Sync Approval basically means "wait until I uncheck this before sending it to QuickBooks". Do you really want this? My guess is that it will fill your QuickBooks with unwanted data - there must have been a reason you didn't want them going to QuickBooks until now (payroll as you mentioned), so this could be a bad idea.
Suggestion: if you don't want to delete them, don't want to send them to QuickBooks, but don't want to see them, why not just create a field called "IsHidden" and set all those values to True, and add a filter to your grid to hide records that have IsHidden?
Paul