Scanning Slides

I am about to start scanning a load of 35mm slides into digital format and was wondering if anyone else has done the same. The main concern I have is about resolution -should I go for maximum res and ignore the filesize or should I go for something say like 300dpi? I have done a test at 300, 350 and 600 and there doesn't appear to be that much difference when viewed full screen on the PC. I don't think I will go to print for too many of them but some of the old shots of friends may want to print out if I send them a digital copy. I suppose they could be viewed on a large format TV in the future but I don't suppose folk will be that close to the screen when watching, so high res may also not be an issue.