My system continues to "not respond" after doing a search & destroy scan, why is this and how can I repair it? I've uninstalled and reinstalled several times but to no avail.

have you suffered a recent virus attack? if so, the infection may be more than spybot is capable of handling alone... also, if you have any other spyware removal suites that could be interfering, i would disable or uninstall them before running a scan again.

Yes, I did have an infection and I am running McAfee. Disable McAfee b4 running the next scan, then?

You will be doing yourself a favor if you uninstall Spybot if it is 1.30 or before... It simply does not have the power to do battle with real infestations... it is basically a cookie cleaner.
Suggest you run a scan with Avira after updating it, then SuperAntiSpywre and MalwareBytes, as well as Windows defender.
You can lave McAfee on there but do not run it, until after you have the results of Avira... then you will know if it is doing the job.

The latest Spybot I'm running is 1.62...I'll try it again since disabling McAfee.

I found malwarebytes to be really good usualy cleans up most infections

Suggest you look in the Event Viewer for Error corresponding to the "not respond":

Start> Run> type in eventvwr

Do this on each the System and the Applications logs:

• [1]. Click to open the log>
  [2]. Look for the Error>
  [3] .Right click on the Error> Properties>
  [4]. Click on Copy button, top right, below the down arrow >
  [5]. Paste here (Ctrl V)
  [6].NOTES
• You can ignore Warnings and Information Events.
• If you have a recurring Error with same ID#, same Source and same Description, only one copy is needed.
• You don't need to include the lines of code in the box below the Description, if any.
• Please do not copy the entire Event log.

Errors are time coded. Check the computer clock at message time.

A note: McAfee is probably your antivirus program. Spybot S&D is an anti-malware program (spyware/adware). I would encourage you to leave the AV running as if you close it, you make the system vulnerable.

IF you do find a need to disable the AV, make sure you are working OFFLINE.