|Can you give a bit more info please:|
Your spec says Windows 7 but you posted on the Windows 8 forum - which is it?
What browser are you using generally?
What is the important program?
IE doesn't usually stop programs unless they are online. In which case you could use an alternative browser, such as Firefox.
This is the direct answer to your question (for Windows 7):
Be aware that you will no longer get Windows Updates (well, the manual ones at least).
I just wonder if you really need to do this.
I overlapped with #1 (took too long to type LOL).
Always pop back and let us know the outcome - thanks