Slow System Start after upgrading vista to windows 7

Hi,

I have a dell studio notebook (4 GB RAM and Intel Core 2 Duo CPU T6400 @ 2GHz) and upgraded from vista to windows 7 without any problems (with dell upgrade cd and win 7 cd). I did not install any additional programs, but the problem is that after the login it takes ages until I can open a programm e.g. firefox. It seems that windows would start hundreds of services or programs in the autostart. I checked that, but there is nothing unusual.

It takes quite a long time until the maintenance center symbol (little flag) pops up, the speaker symbol and the homenetwork icon is created new on every system start on my desktop. After that, windows is running quite fast.

Vista started quite fast but with windows 7 it takes ages without installing anything additional.

I think registry booster won´t help because it is only the time frame after login until I can start to work. The boot procedure up to the welcome screen does not take 2 long.

Anyone has an idea what I can check / do?

Thanks in advance,

Frank