out of interest, can you select a different path?
Nope not directly (you could use a proxy server somewhere on the web and set static routes to that but that is beyond the scope of this issue

). Your PC directs traffic that is not on its own subnet to the default gateway (your router usually). Your router will then have the ip of where to go next (or it will broadcast it out to your ISP).
From there its wherever the comms equipment on the web takes you. Obviously there are algorithms in place etc to route you the right way.
In hzza's case if we find a suspect link that is owned (controlled by) by his own ISP then he can raise an issue with them to sort the suspect kit out.
We recently have seen issues resolved where the ISP (easynet in our case) have routed traffic down other outes to improve latency and reliability.... that is business class line though. Whether you get the same support for home broadband, thats anyones guess. If not the solution would be to move ISP although depending on where the issue is this may not solve it either.