Many of the applications that runs on XP runs on Win 7 too as is..
Some will Not.
Solution get the free XP VPC Mode.
It is a download of Win 7 VPC + Ready made inage of Win XP that goes into it with a free Lic.
The Computer need a cpu that does VT, and run Win 7 Ultimate, Pro, or Enterprise.
You can use CPUID to find out if you CPU does VT.
If it shows VT (as above), it does VT. CPUID would check AMD CPUs for Virtual capacity too.
Microsoft page,
http://www.microsoft.com/windows/virtual-pc/download.aspx
When insalled and running Looks like this.