I’m confused about the whole “clean install” terminology. Can I do a clean install of Windows 7 Home Premium Upgrade box? Or do I need to buy the whole version to upgrade my current Windows Vista Ultimate?

I am looking to buy a laptop, however I can wait because I have my old laptop. Would it be wise to wait for windows 7 to buy a new laptop? Or should I go ahead and buy it?
My current laptop has XP. I have no problem learning new OS. I already have worked on Vista.

If I remember correctly, Microsoft is cutting XP updates April of this year.? If that is true it would be a good idea to upgrade but why upgrade to Vista (downgrade really) if 7 will be out this year or next year and then have to upgrade again. Should I wait? Should I buy Vista and then upgrade once 7 is out.???

I am looking at a new Dell XPS to replace my current XPS.

Thanks for the opinions.
I do not think it would be real good to have 98 again. Most of today’s software is geared toward XP and Vista.
Yeah, my problem with Vista is I do not like the hard startups and shutdowns. I have a newer laptop I got at the beginning of 08 and I just do not like it…I get all kinds of errors and alot of software that I got with the laptop does not work properly…Why buy something when something else is coming out within a few months to a year.