[HELP]Macbook Pro can't start up and slow

[brianlhp]

First of all, in the recent days my MBP runs extremely slow. And now it even can't boot up! I tried to reinstall my Lion using the Recovery Disk but it said "Can't download components"<-- something like that...
And now I don't know why i even can't boot my Mac, and I also can't boot to my bootcamp partition(windows).
I tried all methods on the internet that people mentioned.
Please help me. This problem annoyed me a long time already.
PLEASE!

-----For your info-----
MacBook Pro 15"
Early 2011, Lion(10.7.5)
750GB HD, 4GB RAM

 

[justperry]

Seems like a dead HD.

What happens if you hold Shift at start up, it should get you into safe boot, or hold the option key to choose the disk you want to start up from.