Upgrading Laptops from Vista to Win7

[Abberation]

My father in law has a Dell Insperon 1525 and my wife has a 1521 both with Vista. They run slow as hell and Vista just outright sucks a elephant cock. So Ive been trying to upgrade the 1525 first but it tells me I need Service Pack 1 first. Trying online it keeps giving me an error message. So I downloaded the pack from Microsoft (BTW I find it odd that it says 10.8mb when Windows update tries to get it yet it was 544mb to download it) and I get an error near the end of the hour it takes to update it and it tells me to fuck off.
So is there anything I can do to get around this?
Or should I just install a new Windows and go back and delete the old one afterwards? On my computer thats what I did but I had XP and it was messed up to the point that I couldnt use it.

[Tentonaxe]

i always prefer wiping the drive instead of upgrading from old to new.

If that isn't an option, you can dig around on the windows update site and download a standalone version of the service pack.

[MinkyMoMo]

The 2 lap's as 2GB in ram and 160 Gb in hard disk ?

Install windows 7 home premium but don´t upgrade windows vista and no delete the recovery partition . Windows 7 new install backup all folder domuments,images an other datas if found some old windows version and save under the folder windows.old.

With a 1GB in ram is better instal windows xp, ther are some guides in internet with how install the necessary drivers.

If you need a valid and legal xp professional serial send me a pm, long time ago buy a 30 xp professional licenses and only use 23 of then.