ttophone

Hi I downloaded "FebCTP_5308_32bit_Main_Staged_DVD" from some download.microsoft.com place and I installed it. My computer has 700mb ram and a Raedon 9550SE graphic card.. so it cant really support it. It lags like hell and I cant even play any games... so uhh I was wondering if there is anyway to reformat or reinstall windows xp back. I did about 3 hours of googling and tried everything. I noticed that there is a way to reformat.. but I could not figure out how to reformat. Here is a couple of methods I tried to reformat.. I restarted with my windows xp recovery cd, it didnt find it. (it didnt even say press any key to boot from disc, just loaded vista) I even tried F12 and chose the CD rom boot.. and that didnt even work. I tried to use disk management but I only had like 8mb accolcated or something and I did make a new volume of it.. and its F: but it doesnt have any files and I dont know how to boot from that. I tried to boot from some floopy thing, but I didnt really know how to set one up and it didnt really work. I tried to boot from safe mode with command prompt and type format c: but of course those files were in use so it didnt let me.. Also some info, here is my boot thing... turn on comp dell logo 2 options show -Legacy (pre-longhorn..) -I choose this, then two more options (its before when I had win xp, it worked) -Windows XP Pro (what I always chose, when XP worked fine) -Windows (never worked) -Microsoft windows -after this, it just loads up vista.. Whenever I choose the pre legacy thing, none of the options even work.. just a black screen =( I dont even care about all the files on my comp.. I just want to get a clean xp do it all over.. please if there is any other method of reformating.. please tell me! Thank you.