I currently have a Dell Dimension 9200 (E6400@2.13GHz), 4Gb DDR2 RAM (4x1GB; 2 running at 400mHz, 2 at 266mHz) and a 256MB Radeon X1300 graphics card.
From my basic knowledge, I know that the 2 RAM that can go to 400mHz are not due to the 2 at 266mHz. I also understand that this PC probably couldn't play Blu-Rays if I buy a blu-ray player.
I am looking to buy a whole new PC. However, mMy question is, for a non-gaming PC that I only wish to run Internet, Office and the occasional (basic) video editing/burning, should I go for the fastest CPU I can afford, increase my RAM to 8GB or get a better graphics card?
Should I go AMD (X4 640) or intel (Q8400) or something else all together?
You don't need to do anything. Your internet and word processing speed won't increase with more ram or a faster cpu. If anything, I recommend a 32 gb ssd if you can find one new for around $60 or less and have all your original windows installation cd's. Or you can clone your old drive if you don't have too many files with maxblast 5.0 or similar software. Cloning a drive takes about 20 minutes.
Cheapest upgrade might be a low end video card with hdmi port on the card. Some of those play blueray. The blueray internal dvd burners have been less then $100 recently, but I've never used one. The blueray internal dvd players might go for $60 on sale. The 4670 chipset video cards will also run without a power supply upgrade. Higher end cards sometimes require a stronger ps.