Computer keeps "losing" my hard drive! Help?

Hi all

Hope someone can help. I have a 1 year old (today 6/1 Velocity Micro Gamers Edge 1000. Asus A8N SLI-Nvidia nforce 4SLI MCP PCI Express w/DDR, 939 PIN, AMD Athlon 64 3800+, 1.5 gig ram, 512 MB eVGA Nvidia 7600GS video card, 160 gig Western Dig WD1600JD 7200 RPM Sata/150, 8 MB Hard Drive, Lite-On DVD/CD RW, 1.44" Floppy disc drive, Windows XPSP2. Hope that's right and enough info?

OK, so in April it did this and it did it again tonight. Turn on computer, all fine. Suddenly everything freezes, becomes unresponsive, can't even use C/A/D, have to hold the power button to turn off. Then when I turn it back on, I get the first screen with the DEL for set-up, F8 for Boot, next screen alot of stuff comes up and at the bottom in all caps -- Disk Boot Failure, Insert System Disk and Press Enter.

So the first time I tried this. Went through set-up, I hit R for repair, got another screen saying Setup did not find any Hard Disk Drives installed in your computer ... Setup cannot continue. ... Got out of that, puter rebooted itself, tried to boot through, ended with a black screen/white lettering:

Pri. Master Disk DVD-RW, ATA 66
Pri. Slave Disk None
Sec. Master Disk None
Sec. Slave Disk None

First SATA.Master Disk LBA, Sata 1, 160 GB
First SATA. Master Disk HDD S.M.A.R.T. Capability Enabled

and at the bottom of that screen, a message saying:

A disk read error occurred. Press C/A/D to restart.

This loop went round and round till I hard shut down again. I'm NO techie! I just wrote everything down that appeared on each screen.

Turned computer back on, hit F8 for Boot Menu

Select a Boot First Device
Removable - Floppy Disk
Hard Disk - 1st SATA-M WDC WD1600JD-00HBB0
CDROM - 1st Master Lite-On DVD RW SHW-160P6S
Legacy LAN

So, selected Hard Disk, 1st SATA-M, enter, got the screen saying Disk Read error again!

Finally, went to Boot Menu (after waiting over 2 hours for tech support to call back, and they still haven't going on 4 hours). I did this:

Boot Menu
Boot First Device and I chose
1 Hard Disk
2 Removable
3 CDROM

And it booted! What I'd like to know if anyone is familiar with VM, with this motherboard and/or harddrive is ... is this something that I'm going to have to figure out what to do on a regular basis? Someone told me that the Asus mobo has a bad habit of "forgetting" your settings.

When I changed and was able to finally get the computer to fully turn on, did I choose the right order? I thought if you have a floppy that that was supposed to be the first thing for Booting, not the hard drive. So I'm really confused, frustrated, unsure if there's just a bug to learn to live with, if something's going on that needs looking at or what.

Any info, suggestions, thoughts, instructions from all you wonderfully smart and tech savvy people is very much appreciated.

Thanks!