LinuxQuestions.org - help! partition problems!

A day ago, I installed red hat linux 7.3. To do this, i wiped out my windows partition, because it is recommended that i install windows xp after i install linux. Anyway, I do this, and i can't install windows xp without deleting a partition. I see my swap partition, which is only about 50 meg, and then my 6 gigs dedicated to linux. And then, i see a partition that takes up 500 meg or so. I thought it was useless at the time, and deleted it to make that third partition my windows partition. This was probably a bad idea, but anyway, to make a long story short, I can only boot into windows, and there is no multiboot screen selection on boot up like the windows xp installer promised. I can only get into windows. I still have the remaining two partitions that are not being used. There is also another problem. Whenever i put in my linux disk and reboot, it gives me an error, saying that some of my windows files are corrupt. While I know it is saying this because I messed something up in the partitions, can I format the partitions and start all over again with linux, and use lilo as the boot manager? Am I screwed? Do I have to format and start all over again? Do I have to put the partition on my other hard drive (i very well can do this)? Please help!