Laptop Acer Aspire 5315. On Windows Vista start up, after the blue Windows Welcome Screen, goes to Black Screen with moveable cursor and stays there for approx. three minutes before continuing start up.Total start up takes around five minutes and computer performs perfectly thereafter.
Have tried:
Start up in safe mode
Repair using recovery disk( also Acer Master Disk)
Cltr +Alt+Delete on Black Screen and entering New Task... explore
"... explore.exe

Although there may be no connection between the two, another problem is that on the command 'Restart' ,after the Acer Screen the start up blocks on a black screen with a small white line on top left corner and momentarily this message appears:-
Try NTFS5 : No zhgrldr
It then requires a manual close down and a 'cold start' (taking a further 5 Minutes).

Sounds like it's time for a complete rebuild.
Back up and then restore windows from scratch..

Thank you for your quick reply Curlyben and pleased to know that you are still there answering queries.
Your answer confirms what I was thinking as the final resort (but hoping not to hear!).
Since I can still use the laptop for the moment and it starts up without delay when on 'Hibernate',I will do what you advise in a short time when it is convenient.