sql server sql express

I can't remember having seen a limit on the number of databases. Each database is maxed out at 10 gb.

check the official limitations: http://msdn.microsoft.com/en-us/library/cc645993(v=SQL.110).aspx

its for a small estate agent where they run act 2013 and cfp both on separate win 7 boxes, i wanted to put them both on to one member server, about 25 users

no problem

i would probably use server 2008 r2 then hypervisor then server standard 2008 again (1 +1) loading sql express 2012 in it
so no probs loading multiple separate instances with express ?

Why would you create multiple instances? Just need to create multiple databases in the same instance

yes i meant that, so am I correct with the hyper-v idea

I hope you don't want to run 25 hyper-V sessions on a small server? Running 25 users on one hyper-V session running SQL Server Express is fine.

no, there are 25 users, sorry if I didn't make myself clear

Running 25 users on one hyper-V session running SQL Server Express is fine.

Would the cheapest way would be server 208 r2 standard, the client already has an SBS 2008 server which is running very slow as it's running sql exp studio 2005 for the ACT 2012.
The server is limited to a max of 8gb ram is now having a hard time that why I wanted to separate  rge sql onto a new member server

That's a good idea, and should help much. You should try to remove anything non-SBS from that server, as SBS itself with all the available services is a RAM hog. MSSQL gets slower if it can't aquire enough buffer memory to keep frequently used data in memory.

so is it 2008r2 or is 2012 better ?

Act! 2012 should use SQL 2008 ... Express if you don't have SQL Standard (or better)

But, you said it's SBS - that means Exchange, which will take all the RAM it can

Also, you said there's an 8GB limit ... what's that limit from?
Plus, what drive sub-system are you using? Faster drives will make a great difference in SQL