My Mozilla Firefox OR Internet Explorer won't open!!!?

[Hayley]

Okay i am going to try and explain it in detail and i really hope any answers are in full detail and explained fully on how to solve this.
I am on the internet on my sisters laptop.
my laptop was completely fine until yesterday night when i decided to go on the internet using my Firefox shortcut. it had the little loading sand timer next to the mouse for about 3 - 5 seconds then it just went off like it had loaded but nothing came up at all. i thought it was just taking a while to load but it never usually does so i tried about 4 more times and it did exactly the same thing again. i gave it 20 minutes and checked back and no luck. i tried internet explorer as well (but i NEVER use it) and no luck that wouldn't open either. i restarted it 3 times and then shut it down and turned it back on 4 times and still nothing. my skype and msn and things like that still work. (ALSO when it shuts down it comes up with the ''end now'' thing and nothing is open even my task manager says nothing is open)
i left it till this morning and then turned it back on and tried both mozilla and explorer again and still no luck. i decided to do a disk clean up and then a disk de-fragmenter and it didnt help?! i have researched it and nothing is helping me because all of the questions asked are either (mozilla isnt working and explorer is) (mozilla and explorer arent working but a message is coming up ((which it isnt for me)) ) or its just about explorer.
ive tried the explorer disabling add-ons and stuff like that and then trying to run both and then enabling them again and trying but still the same thing happens where it doesnt work.
im really really stressed because im a real noob when it comes to these things, my laptop is literally my life and has practically helped my through stressful things (actually youtube has but i need my internet for that) and for coursework and homework and exam revision and ive had to go on youtube on my phone but its slow and buffers all the time and its bad quality and i dont have revision book i just have to go through my notes.
PLEASE PLEASE PLEASE HELP! :'(

i really need practically professional help (or someone who actually really knows what they are doing i dont want ot do something that MIGHT help but makes it worse...) because i used to go to to a man who had an IT shop down the road from me but he closed it down so now i dont haqve anyone else to help me !

im only 16 (in 5 days...yay) and so yeah i need things explaining in as much detail as possible!

if you need any other details or anything just ask and i will try my best. i have done a virus scan using microsoft security essentials and no threats have been detected (i run one every week) i go on it every night for like 5 hours or something and i'm having separation issues! (my laptop is an lonovo thinkpad Tseries if that helps and its windows PLEASE HELP! i have tried getting on firefox many different ways like programs then firefox the shortcuts i have and same with internet explorer and i have also tried safemode and still no hope
how am i supposed to download firefox again if i cant access internet!!!

[Cheeky]

It could be that when you opened your LT it updated and that is why you cannot open the internet.

Go into computers then into programs and look for the firefox folder click on it and see if there is a firefox logo and click on it to see if it opens the page if it does then you can delete the desktop logo and then right click on your mouse and when the window drops down click on copy you can then close the folder and right click on your desktop and save. you can do this to internet explorer.

If it does not open or you cannot find firefox etc go into your control panel and click on add and and remove look down the the list to see if they are there if so then you still have them on your LT you can also go in to search in start> search and look for them.

you can also go in to control panel >internet option and look to see what address you have in the large box if it is blank click on default this should bring your home page back. if it doesn't you can then add you home page addie .

If that fails then go into computer >accessories>system tools and when the calender comes up click on a date before you lost everything then ok. your LT will close down and reopen and with any luck it should all come back.

If that fails then you will have to download firefox again

Have a happy 16th birthday