I have a free script on my website and in a few months i want go to a paid script. I was reading the terms of service and it said "Furthermore, any and all links to the free script must remain in place and may not be removed under any circumstances". With me going from a free script to a paid script is that special circumstance? Do i always have to keep their link on there? Do i have to get new domain and start over? The free one is very limited in features and the paid one is way better.
You should e-mail the creator of the script about it. Sometimes when you pay for a script, you get to remove those kind of links.
If you no longer use the free script at all, then you are not bound by the terms of that script. You will be bound by any terms of the script you pay for though. If you use both of them, you will need to abode by both sets of rules.