bitref . com
do not use these unknown sites i suggest you only use popular online block explorers to check your balance. use blockchain.info blockr.com blocktrail.com
as for a solution if you don't want to continue running core in full mode, go to pruned mode (which i think should take 2 GB space) i have never done it myself so wait for someone else to explain it if you want to do this.
or you have another option to move to an SPV wallet like Electrum which will only need less than 50 MB download. just export your private key and sweep it in Electrum after you installed it.
Just to verify: i run bitcoin core in pruned mode, as of today, it's using 2738380800 bytes on my disk (=~ 2.54 Gb).
You do have to download and verify all blocks, so pruned mode does not shorten the timeframe to sync your wallet, it only lessens the disk usage.
The easyest way to run core in pruned mode is to create a file bitcoin.conf and put in this line:
prune=600
On windows, the file usually resides in this path:
C:\Users\<youruser>\AppData\Roaming\Bitcoin