I suppose you have your firewall and antivirus software updated daily… And check for Windows updates very often.
Anyway, the delay on startup could be due to avast providers start up and scanning the startup items.
If you are an advanced user, you can exclude some files of avast scanning. Be careful.
Other thing is use a StartupDelayer to control the order of the startup programms as Windows does not have one (http://www.r2.com.au/index.html)