deleting older version of SpyBot S&D

I deleted an older version of SpyBot S&D via the add/remove programs function of my windows Vista. I do NOT think I was prompted to reboot after the removal, so I did NOT Reboot. I was able to install the latest version 16.?
Since I was able to install without issue, can I assume that my current version is running correctly? I use it as an on demand scanner and not as real time protection. I was able to rund several scans with no issue.
So do I have to reboot???

The only reason a reboot would be required would be to unload resident modules that were still in memory. Having installed the latest Spybot and confirmed the status of the resident modules is disabled (if that is what you wish) - then everything should be fine.