My Mac is dying.

Right, I've had my Mac for around a year now, its starting to have some serious lag and crashing issues. I've gotten to the point where my mac is almost useless if you want to do anything except use the internet. Games, apps, anything that is resource demanding lags.

I'm pretty annoyed since this computer was bought for £2,000, thats right, £2,000 and it can't run BadPiggies! I'm seriously wondering how this machine's gaming power is beaten by a bloody £15 PS2!

I also forgot to mention I have bootcamp installed with a couple games windows-side. Doubt this is the culprit since I could run most of my games without a hitch when I had this installed, its only gotten bad today.

I desperately need help!

About This Mac-

Mac OS X Lion - Version 10.7.2
Processor - 2.4 GHz Intel Core i7
Memory - 4 GB 1333 MHz DDR3
Startup Disk - Macintosh HD

Hmm sounds like you've got to the end of your tether dear boy...can you enlighten us with any maintenance regime that you have in place, what resource demanding applications that you use and how much HD free space you have?

Ok, I don't really 'maintain' it. I do regular re-boots (not hard ones) every day and I tried using a time capsule but when I thought I set it up it didn't seem to work and it was too much of a hassle to do.

Whenever I open one of my games I have nothing running in the background except Safari sometimes if I want to listen to music.

Recently, due to crashes, I've been doing many hard reboots, could this have messed up the computer?

Macintosh HD - 210.69 GB free out of 347 GB

BOOTCAMP - 318 GB free out of 375 GB

I must've done an exceptional job of screwing this one up...

Also, I've tried hard resetting it 3 times. Once when I loaded up NFSMW and lagged my computer to death, the second time after when I crashed in Gmod and just now to see if I will fix it. None solved it.

Ok, I've tried again and now it works. After countless retries it fixed itself. Sorry if I wasted anyone's time.