PowerPoint can't sort tables, unfortunately.
You might want to use Excel instead. Enter your data, let Excel do the sorting and formatting.
Make sure you've saved the workbook to the same folder as your PPT file.
When it looks the way you want it to, select just the "live" part of the worksheet, the part with your data.
Then rightclick and choose Copy.
Switch to PPT, choose to Paste Special, put a checkmark next to Link and choose Microsoft Excel Object as the paste type.
The Excel data will paste into PPT, retaining its formatting and will be resizable w/o distortion.
You can double-click it if you want to edit the data in any way (it'll be editable in Excel).
What you do next will depend on whether you need to distribute the file to others and whether you want them to be able to continue editing or not. Fill us in on that and we'll go from there.