Hi Welcome to FixYa!
If you are having this kind of problem, follow the steps below:
1)Turn off the computer completely.
2)Unplug the charger from the laptop and remove the battery.
3)Press and hold down the power button for 5-10secs. (this will drain the remaining static charges inside the computer)
4)put in back the battery and plug the charger back.
5)Try now to turn on the computer and see if you will be able to pass the Windows Welcome screen.
6)If still no go, turn off the computer again.
7)Try to boot into safemode. (Turn on computer and once you press the power button, keep on tapping on F8.. You should see a screen that has Windows Advanced Boot Options. It has different options like safemode, safemode with networking, etc.)
8)Using the arrow keys, select Safemode. You should be able to login into Windows in Safemode.
You might notice that the resolution is different. Don't panic, that's normal.
9)Once you are in safemode, access the System Configuration Utility tool. Open the link to know how to access it.
10)Once you have accessed msconfig, click on the startup tab>then click on Disable all>click on apply.
11)Click on the Services tab>put a check on the box that says, Hide Microsoft services>Click disable all>click on apply and OK.
12)it will now prompt you with a restart. Restart the computer. and it will now boot back to normal mode.
13)You should be able now to access Windows. If it is successful, there are just some startup items or services that are having conflicts while Windows is trying to load up.
If you are not able to access safemode either, pretty much you have a bad hard drive or Windows could be corrupted. Try first reinstalling Windows on you computer.
Hope this could be a big help.