explorer 11

Hi,
I am new to the forum, have a 10 year old desktop.
I recently changed from XP to 10 had lots of problems so installed 7 instead, was working fine but some sites said the my browser was out of date, searched and downloaded explorer 11 only to find it was not compatable.
I tried to change to 9 but it didnt work, so now 11 is not working and I cannot access internet to put it right.
I am using my tablet now, which is ok, but I cannot download anything as it hasn't a usb socket.
Please can anyone help?
thanks Barry

Thankyou both,
I got windows7 via ebay with the code, downloaded windows7 from microsoft used the code,
after it finished it worked fine until some websites said my browser was out of date.
also everytime I went to shut down it said there were updates 183 in total, so it must have been a basic one?
I tried explorer 11 but was told an earlier explorer was better, downloaded explorer 10 but everything stopped.
I cannot get onto internet to put things right.
Have reinstalled 10 but it says there is a driver missing, put in a driver collection cd but that doesn't work either.

will try going back in time to when it worked?

Thank you Barry

Thanks,
I tried again to go back in time and it worked fine.
I did try before but it didnt work so I had a problem.
I looked on youtube typed in "explorer 11 broken on windows 7" watched a video who went on to a part of the OS I coulnt find before which allowed me to choose a date which worked before. using my tablet.
The problem I have now is the explorer 8 is out of date, but I dont know how to update to another browser without getting my PC all mixed up again.
Barry

Thank you,
I tried to download explorer 11 as you said but after about 10 attempts I gave up and deleted internet explorer altogether.
I will use chrome and firefox in future.
Perhaps I am thick or something?
Barry