I've been hearing more and more about the importance of regular defragmentation. These days many more people are downloading large files, often fragmented (like .torrent files), which is contributing to slower access to their hdd and therefore slows their computer speed down.

I've never been bothered until recently, when I happily discovered that running defrag once to twice a week makes a huge difference! Only problem of course is that it has to be done at night and everything else needs to be shut down meanwhile, as otherwise windows will re-start defrag 10 times!

So, can anyone recommend a good alternative way of dealing with this?

Dealing with what? Not having to defragment? Or not having to shut everything down and defragment?

You can do a boot-time defrag so it will defrag before windows even starts. I've used perfect disk (i hope thats the name) before its much better then the windows defragmenter.