are you simply looking to buy a board that will run the processor and ram without any overclocking what so ever? if so that board will probably work okay. i honestly would buy a p35 chipset though just because they have better preformance than the older G31 and they dont usually come with that annoying (and horrible) onboard video adapter you just disable in bios anyway. im an enthusiast though (i would buy a C2E nehalem on launch date 09), and i usually dont spend anything less than 150 on a board.
also, with $250 you are REALLY cutting it tight for what you can get, espescially since the LGA775 socket is going to be obsolete this time next year. if i were you i would honestly find a board you like now (a good one, like a 780I FTW from EVGA), and get an e8400 and some good overclocker ram. the mainstream nehalem processors arent expected untill late 09/10 sometime, and there is talk of an LGA 1166 or something socket for the mainstream processors, and an LGA 1366 socket for the high end ones, so if you buy a hot rig now it isnt like you will be blowing a ton of cash on something that will be dirt cheap in 1Q 09.
with all that considered, here is the best i could come up with that isnt far out of your price range. anything else would be a waste of money at this point.
Newegg.com - Intel Core 2 Duo E8400 Wolfdale 3.0GHz 6MB L2 Cache LGA 775 65W Dual-Core Processor - Processors
Newegg.com - Patriot Viper 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory - Desktop Memory
Newegg.com - GIGABYTE GA-EP35-DS3L LGA 775 Intel P35 ATX Intel Motherboard - Intel Motherboards
also, i couldnt find any boards i would consider acceptable for a gaming computer in micro ATX. what i chose there is what i would consider the bottom of the market right now for a gaming rig, save the cpu, which is the best bang for the buck you can get right now. all the "budget" cpus out now arent half as good, and they are comming out with a 45nm cpu soon anyway which will replace all of them at the same price point