You are pretty much stuffed without a CD. Doing the F8 might allow you to boot into either a) Safe Mode (if you are really lucky, probably not) or b) Command Prompt only (again probably only if you are lucky)
If you can get that far.
I guess you didn't make any backups ...... (two types of people in this world those that have lost data and those that will lose data)
Your probable solution is to get a recovery or rebuild CD from the manufacturer (which will wipe EVERYTHING on the disk - all data) - sometimes they are free, sometimes you have to pay a nominal fee, sometimes the manufacturer doesn't supply them, if the latter, then you are really stuffed.
Surrey Boy, June 2008