Windows 7: Problem installing windows 7

hello everyone,i need help so please do your best!I have tried to install windows 7 in my PC several times (in my laptop worked just fine) but all of them failed.i put the disk in and on the screen appears "windows starting" after a while but they never start.the dvd rom's lamb is going green for a little while and then goes off again and the dvd stops.i have tried to eject and put back the dvd but it's going nowhere!i have left the dvd for hours inside but still no responce...i m gonna birst into tears so please help me!
[2Gb ram, 4200+ dual core amd ,nvidia 7600 gt]
i think its either dvd rom's fault or bios...

are you using the same DVD that you used to install Windows on your laptop?

Try removing the sound card and see if it installs then.

Do you think your DVD drive is bad?

I m going to try your way and i will tell you the results in a little bit.i think that the dvd drive stops reading the dvd without reason in this situation but i ve never had problems from its use

see if it will boot from the XP install disc, or anything else for that matter (e.g. some Linux "live" distro). If it works, that should eliminate the DVD drive as being the problem.

Check your BIOS settings.. make sure that your DVD drive is set as the first boot device...

Are you trying to install 32 bit or 64 bit version?
I have a AMD 4200+ in a machine and I have never been able to install or run Windows 7 64 bits on it. I run 32bits (I am writing from it right now) and I have installed and run Vista and Ubuntu 64 bits, but Windows 7 won' t work. I replaced the processor and it worked fine, so it is the 4200+.
It might have been just mine that has a problem (although that seems to be the only problem with it) but it can be some design flaw.
Try 32 bits if you can
And welcome to the forums!

Well if the computer is already showing the DVD boot screen I would've thought that is already the case. But certainly worth looking into.

Tews it is first boot divice of course!sup3rsprt fisrt of all its the same dvd that worked well at my laptop.the xp dvd works just fine...so whats the problem with the Windows 7 installing?BIOS? i ve tried removing the sound card but nothing again

Check out wally's post above. Maybe he is on to something there

Have you disconnected all your devices and then tried? printer, usb speakers, second monitor?