Delete content on hard drive partition on inspiron e1505 laptop for re

Last question first: yes.

If you boot from the windows vista install CD, you should be able to delete all paritions and have it create what it needs. Google vista clean install and you should find some good guides.

I'd pick NTFS.

Great! Thanks! I've done the clean install on the larger partition and have tried to install Windows 7 Home Premium Upgrade. It says my product key is invalid. There really isn't any code on the authentic label that has the right number of digits and spaces. I tried it, though. I also tried the original product key on the bottom of my computer. Any suggestions? I see from surfing the web this is a problem. I'm not finding any great conclusions though.

The win 7 with Dell's I think is tied to the bios to automatically authenticate. At least it worked that way with XP. You probably need the original cd/dvd, or equivalent Dell OEM verion. Get that working then try the upgrade later.

I did use the OEM Vista DVD and had it working. Then I put the 7 upgrade dvd in and it seemed to go in ok. Then when it restarted it wanted to prepare for first time use and asked for a product code and the only code that fit in the spaces was the one on the Dell, but, I got an error message that said it was wrong. The 7 label # looks like this ##########-#-######-XXXXXX or there is a number up under the barcode that looks like this #####-###-###-### and it didn't like either of those. Could it be because I installed the Vista and the 7 upgrade on the same partition but that it was a different partition from the one it was setup on before at the factory?
It seems like the corporations are so worried about being ripped off that people who buy a legit product have to jumped through hoops to get it to work. Meanwhile the crooks are out there with work - arounds using the products for free.

I think the windows 7 upgrade just looks for a prior install. There should be a product key with it, not just a barcode or label. Maybe a little piece of paper that actually says "product key" or activation key, or something like that.