As far as Spybot is concerned, it is not necessary to 'delete' it; just turn off teatimer if you are using that and, if you wish, you can also disable SD Helper (Spybot, advanced mode, Tools tab, resident page uncheck both resident SD Helper and Resident Teatimer).
Similarly, for other antivirus and antispyware programs, no need to 'delete' them, just turn off any active monitoring before installing SP2.