Display and performance problems

Question

Many times cannot power up my laptop the power light and charging light is on fan is working but screen is off I try always remove the battery and press power switch 40 seconds after screen is displayed many times I found this complaint I need a reason
and 2nd complaint is sometimes screen is display only half page wallpaper is perfect but open any applications page only half page I need a perfect replay 3rd complaint is computer is too slow

Answer 1

I'll answer your third complaint first. Without knowing exactly what model laptop you have and exactly what you are trying to do with it there is no way for anyone to have any idea why it's slow. Heck, we can't even tell if it's actually slow, or if you are trying to do something that the laptop isn't capable of doing, or at least doing well.
I have yet been unable to find a definitive answer to why they sometimes don't turn on fully. That's why I posted the procedure to get past the problem. Only Toshiba and the other manufacturers know what the actual problem is, and I haven't seen them post the solution for it anywhere. It is a common problem in all brands and types of computers though, not just Toshiba's and not just laptops. Desktops also have this problem. The best theory I've run across on why it happens is static electricity buildup on the main circuit boards of a computer causing the problem. The procedure I outlined above drains all of that buildup from the system allowing it to boot again, If you have that problem on a regular basis you might want to check into the electricity source you plug into. I've noticed that people who live in mobile homes (with metal outside walls( and people who live in homes with aluminum siding tend to have this problem more than people who live elsewhere. I used to have to disconnect the mobile home I lived in from the power grid a couple of times a year to dissipate the static buildup in the building itself otherwise I had static in my telephone, television, and problems booting like you are experiencing, 
Since Toshiba support personnel are prohibited from posting in the forums it's doubtful that you'll be able to to get a definitive answer from them without calling them on the telephone and talking to an actual support person. They don't provide actual support any other way. All we have here are end users like yourself doing what they can to help other end users.
Your second issue about only displaying half page has normally been a display driver issue from my experience. Make sure you have the latest display driver for you specific laptop and see if that helps. If that doesn't, you might need to download and install a display driver direct from Intel, MAD/ATI, or nVidia to see if that corrects the problem. Doing that can be tricky and since you didn't bother to identify your specific laptop there is no way for us to know what display chipset you need. 
The only other thing that I can think of is that your video subsystem is failing. Either a loose or faulty internal cable, failing display panel, failing display chipset, or some other portion of the subsystem. You could try connecting to an external display the next time you have an issue to see if that works better or not. Otherwise take it to a certified techinician and have it thoroughly checked out.
Also, check the Product Support Link at the top of this page for your specific model. Check the support bulletins for it to see if they list any issues or fixes that might pertain to your situation and model.
If you don't post your COMPLETE model number it's very difficult to assist you. Please try to post in complete sentences with punctuation, capitals, and correct spelling. Toshiba does NOT provide any direct support in these forums. All support is User to User in their spare time.