Ive done some research on building my own computer, but aren't heat sinks already installed on the computer? Also would a decent CFM exhaust and intake fan be enough?. I will definitely be purchasing a video card when I need to for now ill use the built in one. Ill be looking into some different ram should I spring for the 4gb still or will 2gb be enough? I am probable going to boot up XP in there also.
If you're replacing the mainboard and the processor then you'll probably need to change from your previous heatsink and fan. It all depends on what you had before. Make sure your heatsink is rated for your processor and your processor fan matches your heatsink. I built one computer that was water cooled, the system cost around $200 four years ago. Air cooling is much cheaper generally tou can get away with between $30 and $50 for a good air cooling system on your processor. Looking at the pictures from NewEgg it looks like the board you like has a heatsink on the chipset, but doesn't include one for the Processor. The processor you chose has a heatsink and fan with it, but keep an eye on your temps if you can (I usually install a thermometer between my CPU and Heatsink that had a digital read out on the case. I always buy my processors 'OEM' and they never come with heatsinks or fans and generally cost 50 - 100 less depending on the processor.
As far as case ventilation, when you're using Micro ATX you have considerably less space for the heat to dissipate so you want to push as much air through it as you can. I personally use an aluminum case that radiates heat out so I don't have to have as many fans to keep it cool. I still ended up using 2 intake and 2 exhause fans for it though.
Memory is all your call. With 2G you'll be fine running Windows XP and a slew of applications with 4G you could run Vista or maybe Windows 7 whenever it comes out. Old school thought would be 'as much memory as it can take' however today I would say just get the mem you need and leave room for expansion. If you have 2 slots for mem I'd get a 2G chip now and if you need to upgrade later then get another 2G chip. Always leave room for expansion if possible, nothing sucks more than having to replace 100% of your memory because you didn't leave any expansion slots open.
Hard drives you'll have to check your old one (I totally forgot about the move from ATA-100 to SATA.) Depending on the age of your computer you could have a ATA hard drive which won't work in a SATA motherboard. The mainboard you picked out has onboard sound and video so you might be able to junk your old cards unless they're really great cards. (I personally don't do on board because I upgrade my cards on the level of every 6 months.)
I would stick with Windows XP if you already have the disk. I have no ill against Vista but don't see any reason to pay for it if you already have XP especially since Windows 7 is in Beta testing right now.
-RT76