How can I stop my tasks that are normally set up on days like Mon- Fri when I'll be on vacation without having to recreate them or manually stop their aging?
Unfortunately this isn't possible to do at this time. We feel like having overdue tasks is a great way to let yourself know you need to be doing things, even if your on vacation.
If you complete everything before you go then you won't have any overdue items or lose karma, and if left undone, it can easily be completed once your back :)
We might consider adding a pause option in the future, feel free to vote on it in if you'd like: http://todoist.com/Vote/showProposal/1011/