Windows freezes always from past 2 days

Hello,

Okay, I have a HP DV6-3043TX running Windows 7 64bit Home Premium, this is the laptop which I bought around last year in November. From last night, I don't know why but it just shut down, I switched it on again & check the battery was at around 12% so probably thats why it shut off but the hitch here is I never got a notification/warning like 'PLEASE PLUG IN YOUR ADAPTER AS BATTERY IS LOW OR ANYTHING'. Ofcourse, I switched it on and its pretty unstable, keeps crashing a lot. Programs don't open specially when I try to open Firefox or Chrome, everything is just stuck and useless & Windows Explorer freezes completely. Despite closing some of the processes via the system manager, it still is unstable. I ran a batter check via HP's Support Assistant software which comes preloaded with all HP laptops & the status was OK. Somebody help guys, this is super annoying. I can't lose any data since all of them are important plus I need my browsers to work properly specially Firefox since a lot of my passwords and bookmarks are saved in around the browser. :/

Another thing I noticed is that the system is rather getting very heated and hot, I was touchisng under the vents.