I have a Dell Studio with Windows Vista Home premium edition.
Is it possible to upgrade from Vista to Windows 7 without having to pay?
Microsoft says in Windows 7 Upgrade Option
Go therefore to Dell Windows® 7 Option Upgrade Website and follow the wizard steps, and you might find out if you're eligible for a free upgrade.
If you're not eligible for free upgrade you may buy your upgrade from Dell online here, but not very cheap at $199.99. It seems at the moment cheaper to buy the upgrade directly from Microsoft Store, where it's billed as a promotion.
The Windows 7 free Upgrade Option program runs from June 26, 2009 through January 31, 2010.
Personally, for all upgrades of Windows that I tried, I always had too many problems with such process. I would use a re-installation process as a chance to perform a GOOD clean up of my system. By re-installing the system, I can also defrag my hard disk, which is something that is hard to do when running Windows, anyway. Having a GOOD backup is essential here, of course, but this will also leave you with an actual backup of all your files, if you did not already make one on a regular basis.
In all upgrades that I tried, there were too many incompatibilities, options that were not properly upgraded or migrated, that the time needed to re-implement those options from scratch is actually shorter than fixing what the upgrade process could not do. And I must admit this is also true for Linux to a point.
And doing a clean install will give you a faster system than running all existing programs under an operating system which is only likely to be more memory and resource hungry.
Once you have the clean install, all you need to do is reinstall your applications, as you need them. You will end up with only WHAT YOU ACTUALLY USE, not everything you tried in the last 4 years.........