Mouse responding very slowly

This has been a problem since day 1, and I am getting sick of it. In game, when I move my mouse it takes about half a second for the game to move. The same goes for clicking, and even using the keyboard! It really gets annoying when you have to wait an extra half second for you to move after you've given the input. I currently have a Microsoft Wireless mouse, but because the same thing happens on the keyboard I don't think that the mouse is the problem.

Do you have a delay on your computer too? How do I get rid of the delay or at least make it better?

Stats:

Model: HP Pavilion dv6700 Notebook PC
BIOS: PhoenixBIOS 4.0 Release 6.1
Processor: AMD Athlon g4 X2 Dual-Core Processor TK-57 @ 1.9 GHz
Memory: 3006MB RAM
DirectX Version: DirectX 10
Graphics Card: NVIDIA GeForce 7150M / nForce 630M
DAC Type: Integrated RAMDAC
Approx. Total Memory: 1065 MB
DirectDraw Acceleration: Enabled
Direct3D Acceleration: Enabled
AGP Texture Acceleration: Enabled

I don't know what to do. Please help!

well first of all, does this input lag happen outside of the game too?  or any other game for that matter?  i know new wireless equipment is good, but if your hardware is old, it may just not have the technology necessary for no (noticable) lag

No, the lag is only in game. I don't think it is the mouse because the same thing happens with the keyboard input as well. (It's not wireless)

As far as I can remember the only other games that have these are L4D and portal.

Dead Space had a similar lag time for me; fiddling with VSync fixed it.

I've heard that VSync slows down your computer a lot, and I can't spare any graphics card RAM. My video ram is my laptop's main flaw. So does turning on "wait for verticle sync" fix the mouse lag problem?

Try it and find out.