Help pls - AGP or PCIe & what Mobo is best??/

Hi all, new to this forum, so please excuse any mistakes... Anyway i'm in need of some advice. I used to have a good pc system with the following:
Mobo= ABIT 3rd Eye
RAM= CORSAIR DDR SDRAM,Capacity 2 x 512 Mb,Clock Frequency 400 MHz,1 Gb (2x512Mb) PC3200
CPU= Athlon 64 3200+ 2000 MHz 512 KiB 1000 MHz 10x 1.35/1.40 V 67 W Socket
GPU=NVIDIA GeForce 6200 AGP8x 512mb DDR2 TV DVI
PSU= X-POWER 450W
So i had this set up for about 8 months or so when i had a fualt on the Mobo. Sent it to Ebuyer and they just returned my money.
So now i left with all the bits but no Mobo.
My question is what Mobo should i buy now? Should i stay AGP or go PCIe??
I'm dont do much except play BF2 online and a few other games and the rest is just normal pc usage. I'm not into Overclocking so really looking for a Mobo thats good fast and handle what i like, without fussying about with it.
Sorry to drag this out- thought the info the better you can help. Many thanks.