Windows is built somewhat completely different to mac/linux and there is no real single user mode.
If you need to reset an administrator account, there are a couple of things you can try:
1)Reboot your computer and as your BIOS screen shows, keep tapping F8 on your keyboard. This will bring up a menu option list - one of which will be "Safe Mode". From here you should be able to login and change an administrators password. The easiest way to do this is to load C:\windows\system32\lusrmgr.msc and find your user.
2)Look at some offline password editors. Some of the most commonly used ones are mtnioned in this article and include:
- ophCrack
- Offline NT Password & Registry Editor
- PC Login Now
..and many more
3)look into the possibility of resetting your computer - this is a bit more extreme and will reset windows to its "out of the box" settings... including removal of user passwords. This, however, also removes user accounts, apps, data as well - only really to be used as a last resort and only if you have a recent data backup. To complete the Reset Your PC process, access Advanced Startup Options and then choose Troubleshoot -> Reset Your PC.