If Teatimer is disabled,no pop-up boxes will appear about registry changes.If you want Spybot to just do manual scans only,the only other thing besides Teatimer you might want to disable is the bad download blocker bho(sdhelper).
You could disable Teatimer by opening Spybot,click mode,select Advanced mode,then saying 'Yes' to the prompt,then click Tools,then Resident,then uncheck Resident "Teatimer" and you can also uncheck Resident "Sdhelper" there as well,if you no longer wish it to be enabled.
Click mode again if you want to return Spybot to Default mode,afterwards.