Help! A hardware or software change caused inability to boot

Hi everyone:wave I have another situation with which I could really use some help. I know I should just leave well enough alone but.....well you know. I just installed a new hard drive and reconfigured my hardware architecture and it worked fine for a time but now it won't boot. I get that black choice screen with the timer that counts down til you make a choice. I went through all choices with no luck. I'm kind of puzzeled as to why the "last known configuration that worked", doesn't, (work that is).I know there is a way to provide a link to my last post, which details the work I have done to this machine recently but I have not learned this very useful technique yet so here goes...My machine is an ECS P4M800PRO-M with an Intel E6300 DUAL CORE 1.86 I have 2 gigs of DDR2 800meg RAM. It has a 74 gig RAPTOR 10,000 RPM HDD and I just installed a MAXTOR 160 gig HDD partitioned into two 50 gig parts and one 60 gig part my OS is on the RAPTOR and is XP SP2. The primary use for this machine is video editing and it has been a joy since the day I built it. I guess what I need to know is first, How do I retrieve data that was on my Z: drive (Returnil v2.0) when we crashed? Speaking of which, I just installed the new beta version.Could that have had something to do with the crash? It would be wonderfull if I could get this thing to boot but that is beyond my skill level right now. Is there a better way to set up this sys for video editing work ? I need to know if the os and the apps should go on the same drive or what?
What if I installed a copy of xp on one of the other partitions and booted from that. Would it harm C:, and would the os on C: interfere with the new boot process? Thank You for any input you may have. You are all great people and I look forward to your responses eagerly.
SYA. Cmdr Chill