The short answer is: No, it won't. Google works out which country your site is targeted at by a combination of the domain name (.co.uk in your case) and how you've designated it in their Webmaster Tools.
The longer answer is: It might - for better or worse. Nobody knows Google's exact algorithm, but it seems that they do prefer sites that load quickly. If you moved it from an overloaded and slow server in the UK to a fast server in NL, it would probably rank better (eventually). The reverse would also be true.
In other words, moving server may effect the rankings. The fact you are moving country as well is not relevant. But if you haven't yet claimed the domains in Webmaster Tools and designated a target country, it would be a good idea to do so.
If it isnít broken, donít fix it. Are you running into issues with your present provider?
I agree with you there and have been with this provider for 5+ yrs, if not longer.
There does seem a problem, but I don't know where it is, my end, in between, there end.
The problem is, it seems to time out sometimes, or take awhile to load, this happening on HTTP, FTP and Email.
Here an example I was FTP'ing 4 PHP files.
First 3 went fine, but the 4 timed out and so did the FTP session.
HTTP sometimes times out where other sites load.
For example, I am viewing a forum I run and then, I click a post to read and it times out in my browser.
Email sometimes has issues, with long waiting before it connects to check if there is email etc...
I was at first thinking it was my ISP connection going down for a minute or 2, but I am able to load other websites fine, including the hosting provider site, which I believe is in a different UK datacenter.
I am yet to contact the provider, but have started looking around.
I currently have a shared account a HawkHost, but there NL location doesn't have resellers yet, so am looking at StableHost.
A lot of the SEO companies I've dealt with over the past few years say that server location is important and does make a difference. However, I have a client that has been running their US site from our UK based servers for a while now, and they have seen no noticable SEO penalties. I suspect that servers based in certain countries will probably be demoted in search rankings as being a regular source of suspicious sites.