Travelling to the UK on the 25th August and will be heading up to Scotland on the 29th Aug, thereafter zigzagging back down the country until I get back to London for my flight on the 15th Sept.

Can someone help with some info:

Is finding a ride share easy? Any where I can find ads for people looking to share travel costs.

Is bus or train better?

Can anyone help with a reputable bus/train company that offers tickets that have no service date - meaning, I am wanting to play it by ear - not necessarily wanting to travel on certain dates. So if I get somewhere and I like the area, I may stay, or if I don't, I would leave - don't want to be tied down to definite dates.