Which board would be most cost effective depends on the features you want, e.g., 2 or 3 PCI slots, onboard video, firewire, do you want to overclock, do want SLI or Crossfire? Given you're looking at the Celeron, I doubt you'd be interested in running 2 video cards.
I would like to keep it as low cost as possible. I already have a SONY DVD writer, Creative Live Value, Pixel view tv tuner which i am using on my present celeron 2ghz computer
Since all the devices i have IDE/ATA will i be able to connect it to a sata interface on the new motherboard?
You can use SATA drives and PATA drives in the same machine. I couldn't find the D865GSA board on the link but the fact Windows 98 and 95 are listed is most likely because Intel thinks no one uses these programs, at least no one buying a new mobo. I may be wrong but I would think you could run them on an Intel 478 board. Given how old the CPU is I would go with something like the ASRock or Biostar below both $50.
Do you need a new mobo because the old one died? If the old one is still working, I don't think upgrading the board really makes any sense given the CPU. If you want to speed things up, you're better off buying more RAM
Now i am trying to find out about amd processors and suitable motherboards,
I will have to go and find out if AMD Sempron 3800+ is available.
This coupled with the recommended asus motherboard on the amd site
asus m2nbp-vm csm.
Actually just bought that mobo and it was about $85 at newegg very happy with it. If this is for a new system I would recommend going with the AMD AM 2. I don't think it makes any sense to build a new system with out of date CPU. What is your budget? Do you just need a CPU, mobo, and RAM? I.e., do you have a case, PSU, hard drive and optical drive? You will in all likelihood need new memory.