VERY slow loading and stuttering. Help? :(

I don't know much more than the average person when it comes to internal problems in my computer. I am a gamer, and that is the purpose of this computer. Last Tuesday, things started to go bad. Startup of my computer and startup of my games are fine, but when I join a server or go into the game everything loads very slow. YouTube videos were set to auto load at 360 or 480p, but since Tuesday they have been set to 144p and still take ages to load. I'm not sure if that means something, but whatever happened Tuesday caused any gaming/video related visuals to load terribly slow. This started to make me think my graphics card was bad (it is honestly, but it does the job at low/medium settings), but looking at other topics I have never seen someone recommending on getting a new graphics card to fix the problem. My computer is a standard 5 year old pre-built HP "Gaming" computer.

I have checked for spyware/malware and repaired/restored my system without any improvement in how well things load. I assume my specs would be nice to add to this, so here :D (not sure what all is needed so throwing everything that looks necessary down)

Windows 7
System Manufacturer: HP-Pavilion
System Model: VT637AA-ABA HPE-112y
BIOS: BIOS Date: 10/26/09 16:01:30 Ver: 5.05
Processor: AMD Phenom(tm) II X4 925 Processor (4 CPUs), ~2.8GHz
Memory: 8192MB RAM
Page File: 3039 MB used, 13325 MB available
DirectX Version: DirectX 11
Graphics Card: ATI Radeon HD 4300/4500 Series