I've a potential problem as such in that the accounts program I use is 10 years old and SAGE have stated that it won't run on Win 7 or above. Now I got a mate to install it on Win7 and it seemed to run ok however as a backup he suggested (now bear with me as I'm not an expert ) a powerful setup so it can run WinXP in a virtual machine. To upgrade the Accs program is about £500 which I don't want to pay so I like the option he suggested as I'll need to check my archive records from time to time
You could do that - I think you have to buy Professional, Ultimate or Enterprise to run 'XP Mode'.
In all versions of Windows 7, you also have 'compatibility mode' where you can set the program you run to be run in an older emulated environment such as XP. Not as successful as XP mode but can work.
However, if it runs as is, try it. It might be just not 'supported' on 7 rather than doesn't run - which wont be an issue.
Alternatively, if you have the media for your accounting package and Windows, you could rebuild your existing computer a fresh and just install the accounts package as a backup.
Then, depending on how your experience goes running it on 7, you may or may not need to use it. If it proves too unreliable, either keep both machines on or maybe source a cheap laptop running XP (they'll be worth a lot less come 08/04/2014)?
I run a piece of software from early last decade as well as one from around 2005, both natively (i.e. not in any compatibility mode) without any issues on 7 Professional.
I seem to remember someone else on here in the same situation - would be interesting to find out what they did but I can't remember who it was - unless it was you asking previously...