Thanks for more info cheema.
I asked Kamille to come in and help for your upgrade.
As far as your Dad's computer goes everything you listed above: Case, Monitor, HDD, etc is compatible and all. You had originally asked for recommendations so here is some suggestions to help save money so you can maximize your upgrade to your computer.
The HDD is good for the price. Best I could find for the price.
You don't need to spend $100 on your Dad's computer case. Look at these:CoolerMaster Mid-Tower CASEThermaltake Wings Mid-Tower CASE
Here is an ACER monitor that is comparable to the HP one you linked to. It could save you $10 and has similar, if not better specs.ACER MONITOR
According to the specs that I found when I researched the motherboard you listed, and the one you linked to, it does not have on board video. So you will have to use a graphics card. You can use the one you have in your system right now if you decide to upgrade, or here is one that is cheap and will do the job for your Dad.EVGA Video Card
I think the best option, (if you don't use the 8800 GTX for you Dad's computer) is too look on craigslist for a cheap used video card, or pick a cheap used one up at a local computer shop.
I have heard good things about OCZ Power Supplies, but I think you don't need one that expensive or powerful. Antec and SeaSonic are reliable too. Here...(all 500Watts)OCZSeaSonicAntec
Add more RAM if your Dad complains about it being too slow. I couldn't find any DDR 2 675 PC 2 5400 other than 512mb sticks. However, with that said, all the motherboards that come up(even on MSI's website) when I search for the model number you gave don't require DDR2 675 PC 2 5400, so I don't know.
And, optical drives are all about the same. I'm currently going to use a Samsung in my build this summer, but that is because it doesn't have the white writing the LG one has. So I recommend Samsung, or LG personally from years of buying other products from them. You may want to find out from you Dad if he even needs a CD burner or DVD burner capabilities.
Look at this one that only reads cd's and dvd's LG DVD ROM
It is SATA, I don't know if you currently are using IDE or SATA for your drives.
Well, that's about it for me. Listen to Kamille if she wants to change anything, and let her know what you decide so you can have a budget for your upgrade.
Good Luck cheema. Let me know if you have any questions! I will continue to watch the thread and keep an eye on things.