Minolta doesn't make updates because Konica is sold (to Sony?).But you can download Windows Virtual PC (is free software:
http://www.microsoft.com/windows/virtual-pc/support/virtual-pc-2007.aspx )This is Vista-compatible.After install you can start it,and in Virtual PC you can install Win XP,or another system(e.g. Win 98).Install it on an empty partition that you use exclusively for Virtual PC and the program's you run in it.
After installing Win XP (you can install more than 1 system under VPC !) you can,after starting VPC,choose the system of your choice and after startup install your Minolta-software and drivers (or your older games and software that you still want to use).What actually happens is:In Vista you run XP and the applications you installed in XP.After closing XP you return in Vista.
Another option,that will cost you about $ 40 is buying Vuescan ( http://www.hamrick.com/ ).Although this solution wil cost you some money it's,in my opinion,the best.Vuescan supports an impressive list of scanners,also the Elite 5400 (I'm sure,because I use this scanner too),and your scan-quality is much (!!!) better than with the software that came with the scanner!
Why buy an expensive scanner,and use such low quality software while,for $ 40 you can get the best out of this same scanner.I use Vuescan for a while now,and it still impresses me with its scan-quality.The scanner itself is really good;it's such a shame that Konica Minolta didn't put more effort in developping better software.
I hope that my advice wil help you in solving your problem.Greetings:Henk Noordhuizen (The Netherlands).