Most people are delighted when they find out they're due a large tax refund. What they fail to realize is that the government is giving them back their own money, and they loaned it to the government interest free.
Don't view tax refunds as a forced savings program, since there are better ways to save than through interest-free loans to the government. If you're concerned that you would just spend the difference every paycheck, have that amount automatically transferred every pay period to an investment account.
If too much federal tax is being withheld from your paycheck, fill out a new W-4 to determine how many allowances you should claim. Every allowance exempts $3,400 of income from withholding. Don't confuse allowances with the exemptions claimed on your tax return. You can claim additional allowances for items such as itemized deductions that exceed the standard deductions, the child tax credit, and education credits.