Remember that if you're switching motherboards, you'll need to purchase new components including RAM in your scenario. Your current RAM will not be supported with the new board you desire to purchase, which utilises DDR3. Your current motherboard only supports DDR2, which is not compatible on a DDR3 board. With that said, simply put you'll need to purchase new DDR3 RAM too.
Your existing motherboard supports SATA and IDE/PATA disc drives (hard drives, optical disc drives etc.) hence if you're using IDE, your new motherboard won't support them either. You can only use SATA on a modern motherboard, which is the successor to PATA.
Click here to view the difference between SATA and PATA. If you're currently using PATA, you'll need to purchase new hard/optical disc drives too.
Apart from that you should be set. When installing your new motherboard and processor, don't bother installing the GT 210. The GT 210 is an extremely weak card, and is worse than the integrated graphics which Intel provides. You'll be better off without a GPU rather than the GT 210. Install a GPU when you purchase a better one.
P.S. Why do you want an i7? You'll be better off with an i5 and a dedicated/discrete GPU for gaming. The processor alone won't allow you to run games such as GTA IV, a dedicated graphics card with a decent processor will however. Rather than an i7, you should purchase an i5 and a dedicated GPU. Perhaps the following?
PCPartPicker part list /
Price breakdown by merchant
CPU: Intel Core i5-4430 3.0GHz Quad-Core Processor ($184.94 @ OutletPC)
Motherboard: ASRock H81M-DGS R2.0 Micro ATX LGA1150 Motherboard ($46.99 @ Newegg)
Video Card: Sapphire Radeon R7 250 1GB Video Card ($82.98 @ Newegg)
Total: $314.91
Prices include shipping, taxes, and discounts when available
The GPU isn't the utmost high-end, but for your budget it's adequate and will easily run GTA IV closer to high graphical setting.
All the best.