Well, I just bought a Tbird and I got the ECS motherboard. And they are rock solid and very good performers.
I also checked reviews at tomshardware and anandtech, and both sites gave glowing reviews of the boards when it comes to stability, speed, and of course price. The only place where they are somewhat lacking is a few of the overclocking frills.
But hey, do you really think your going to be overclocking a 1.4ghz Tbird much?
I would go with the DDR memory, at least 512megs, but would probably skip the GF3. The GF3 is still too pricey for the performance, so I would go with a good GF2 Ultra or the ATI Radeon 64meg card. Significant savings by skipping the GF3. If you already have a GF2 GTS I would just use it, because it should do just fine with that CPU.
Last night I also just put a new Tbird 1.4 together for a friend of mine, and he went with the ECS motherboard. His is just like mine, great performance for a nice price.
Oh ... just remember there are two ECS motherboards for the DDR memory, the one with the Ali chipset and the SiS chipset. Make sure you get the one with the SiS chipset.