Windows 7: Help! Need to upgrade from RC

Hey everyone.
So I've been running windows 7 release candidate for some time, long past its expiry. I have gone out and bought a legitimate version but now it won't let me boot from the cd! I changed all the settings in my bios to only boot from cd and it somehow still loads from the harddrive? When i insert the cd if the laptops on it doesn't recognise the disk, but i know its not dodgy because i tryed it on my other computer with xp and seemed to work fine.
Could maybe have something to do with a 3rd party boot program i installed when i first got rc that got rid of the option of choosing which op i wanted to load when booting (even though i only had one). I can't seem to find that program anymore. What im getting to is would it be safe to just get a format prgram and wipe the hd partion its on then try load from scratch? Thanks

That is exactly what I would suggest... alternatively, you could extract the files from the Install DVD to a separate drive or partition and run the setup.exe file from there...

Will the DVD start in Windows?

BIOS boot change.
Boot Priority - Change - Vista Forums

The dvd doesn't load in windows. It just spits it out and asks to please insert disk, but the drive runs fine with other dvd's. Thats why i'm a little hesitant on formatting just incase it still doesn't want to read for whatever reason.

Do you have aother DVD drive you could use.

yeah i've a desktop that it seemed to load fine in.

Have you tried a "clean" install" ? Clean Install Windows 7

ah pretty sure you need to boot from cd to clean install. which isn't going so well for me at the moment.
Is there a way i could get everything off the dvd that i need on my other comp then get it onto my other partition and install from there?

extract the files to a flash drive... easy peasy..

naww thanks guisee. will let you know how it turns out.