UAC slowing down startup both enabled and disabled...

After doing a clean install of Vista Premium I noticed that something is
slowing down the startup. If I have UAC disabled my laptop will boot to the
desktop in less then a minute and I can do things like browse my computer.
However, the files in my Startup-folder and any other programs I execute
aren't started. This goes on until after 30-45 seconds, after this everything
works as normal and the programs I ahve previously executed are started now.
If I enable UAC everything is the same except that the programs in my
Startup-folder aren't executed until after this waiting period.
During the waiting period the hard-drive is pretty idle, as is the CPU.
Memory usage can be high though.

Any idea on how to get rid of this unecessary waiting time?

Thank you!